Knights of the Frozen Throne Cards

Howdy! Welcome to my set predictions for the Knights of the Frozen Throne expansion for Hearthstone. These predictions are being done before the set itself is released, so many ideas will likely be proven false by how the meta shakes out. I'm doing this mostly to familiarize myself with the cards. If you have stumbled upon this review, I hope you find it informative as well. Just remember that the ways I see the cards now, before the expansion is released, will likely not be accurate with how the cards are used in the meta. Now, I'll begin with...

Druid

Druid Commons

Gnash

Gnash is a 3-Mana Spell that reads, "Give your hero +3 Attack this turn. Gain 3 Armor."

Gnash is a less situational, flexible and powerful Feral Rage, at the same Mana cost. It's not a bad card, but there's a better Druid spell already at the same Mana cost.

Crypt Lord

Crypt Lord is a 3-Mana 1/6 Minion that reads, "Taunt After you summon a minion, gain +1 Health."

I like Crypt Lord's synergy with Hadronox (the new Druid Legendary Minion that brings back dead minions with Taunt. On top of that, it also makes any additional Taunt minions that you play even better (like Ancient of War, Druid of the Claw, etc).

Webweave

Webweave is a 5-Mana Spell that reads, "Summon two 1/2 Poisonous Spiders."

I don't like this card. It's too expensive, and has no immediate effect. With the slower meta that I believe that KotFT will bring about, there should be plenty of AoE to take care of these 2 spiders. Stubborn Gastropod seems like it will continue to be strictly better.

Druid Rares

Druid of the Swarm

Druid of the Swarm is a 2-Mana 1/2 Minion that reads, "Choose One - Transform into a 1/2 with Poisonous; or a 1/5 with Taunt."

Druid of the Swarm is a potentially good card. A 1/5 with Taunt on turn 2 is really good. A 1/2 with Poisonous on turn 2 is middling. Combined with Fandral Staghelm (a card that enables your Choose One cards to have both effects combined) could make this a 2/7 Minion with Poisonous and Taunt, a 1/7 minion with Poisonous and Taunt, or give both options, which would all be great. It has also been confirmed that the transformations are Beasts, which synergizes well with Mark of Y'shaarj.

Strongshell Scavenger

Strongshell Scavenger is a 4-Mana 2/3 Minion that reads, "Battlerage: Give your Taunt minions +2/+2."

If Taunt Druid takes, then Strongshell Scavenger could see play, particularly combined with the insta-board that Spreading Plague has the possibility of producing.

Spreading Plague

Spreading Plague is a 5-Mana Spell that reads, "Summon a 1/5 Scarab with Taunt. If your opponent has more minions, cast this again."

Be behind on board no more with Spreading Plague! For the low, low cost of 5 mana, you can turn an empty board against those pesky aggro Druids into a board that can challenge even the best Living Mana turns.

Druid Epics

Fatespinner

Fatespinner is a 5-Mana 5/3 Minion that reads, "Choose a Deathrattle (Secretly) - Deal 3 damage to all minions; or Give them +2/+2."

It will be fairly obvious which of the Deathrattles you choose, and that may be OK. With only 3 health, you should be able to fairly easily kill Fatespinner off. Not a great card, but not a complete flop. Just needs to find the right deck to succeed.

Ultimate Infestation

Ultimate Infestation is a 10-Mana Spell that reads, "Deal 5 damage. Draw 5 cards. Gain 5 Armor, Summon a 5/5 Ghoul."

This card is expensive, but it is totally worth it. Dealing 5 damage is good, giving you some single-target removal. Drawing 5 cards is absurd, and will be able to help draw into even more late game. Gaining 5 armor is nice, but typically not integral. Summoning a 5/5 Ghoul on top of it all is just the cherry on top.

Druid Legendaries

Hadronox

Hadronox is a 9-Mana 3/7 Beast Minion that reads, "Deathrattle: Summon your Taunt minions that died this game."

Taunt Druid new meta? Hadronox can be a great N'Zoth-esque turn bringing back dead Taunt Minions that can keep Ramp Druid competitive.

Malfurion the Pestilent

Malfurion the Pestilent is the Druid Hero Card. It costs 7 Mana, gives you 5 Armor, and reads, "Choose One - Summon 2 Poisonous Spiders; or 2 Scarabs with Taunt." It also replaces your Hero Power with Plague Lord.

Malfurion the Pestilent seems a little underwhelming. It costs 7 mana, which seems about right with the other Hero Cards, but the Choose One options seem a little weak.

The two Choose One options of "Summon two 1/2 Spiders with Poisonous." and "Summon two 1/5 Scarabs with Taunt."

Though the Choose One option is confirmed to work with Fandral, which is a big deal, and could make this great.

Plague Lord is Malfurion the Pestilent's new Hero Power. Plague Lord costs 2 Mana, and reads, "Choose One - +3 Attack this turn; or Gain 3 Armor."

The Hero Power is what is truly underwhelming. It's definitely better than the original Druid Hero Power, but does not appear to be quite as impactful as the other Hero Cards. It's not bad, but the power levels of the other Hero Cards make this seem quite underwhelming.

Hunter

Hunter Commons

Play Dead

Play Dead is a 1-Mana Spell that reads, "Trigger a friendly Minion's Deathrattle."

Will Deathrattle Hunter become a thing? This has the same text that Princess Huhuran and Terrorscale Stalker had, but doesn't put a body on the board, and is thus more situational. However much I want Deathrattle Hunter to be a thing, I don't know if there are enough Deathrattle cards in this set to make it competitive.

Bearshark

Bearshark is a 3-Mana 4/3 Beast Minion that reads, "Can't be targeted by spells or Hero Powers."

Not being able to be targeted by spells or Hero Powers is nice. Being a Beast is nice. I don't think that this card will get played much in Hunter, however. This is a big buff to the Hunter Hero Card, though, being able to get a 3-Mana 4/3 of stats, that can't be targeted by spells.

Stitched Tracker

Stitched Tracker is a 3-Mana 2/2 Minion that reads, "Battlecry: Discover a copy of a minion in your deck."

Stitched Tracker is awesome. It's not a Beast and it's understatted, which is a little detrimental, but a 3-Mana Discover a copy of a Minion in your deck is awesome -- it keeps you from losing card advantage with cards that synergize with your strategy, while still putting a little pressure on the board.

Hunter Rares

Venomstrike Trap

Venomstrike Trap is a 2-Mana Secret that reads, "Secret:When one of your minions is attacked, summon a 2/3 Poisonous Cobra."

Venomstrike Trap is OK. Forcing your opponent to take care of another body on board is good. If the Poisonous Cobra had stealth (like Cat Trick, another Hunter Secret), it would be a good card.

Exploding Bloatbat

Exploding Bloatbat is a 4-Mana 2/1 Beast Minion that reads, "Deathrattle: Deal 2 damage to all enemy minions."

If Exploding Bloatbat's effect was a Battlecry, then it would be fantastic. As a Deathrattle, it may be good to keep your opponent from developing more on an already big board, or bait small removal. It's too expensive for its body and effect, though. I think this is fluff to provide Build-A-Beast with more options.

Corpse Widow

Corpse Widow is a 5-Mana 4/6 Beast Minion that reads, "Your Deathrattle cards cost (2) less."

More Deathrattle synergy. Another Beast (buffing the Hunter Hero Card), solid stats. If Deathrattle Hunter becomes good, this will be an auto-include.

Hunter Epics

Toxic Arrow

Toxic Arrow is a 2-Mana Spell that reads, "Deal 2 damage to a minion. If it survives, give it Poisonous."

Toxic Arrow is a very flexible card. If you only need to additional damage to finish off an enemy minion, you can do so with Toxic Arrow. If you are against a large minion, you can take it out by damaging your own minion that would run into it anyway, and ensure that it kills off that large minion. I like this card a lot.

Abominable Bowman

Abominable Bowman is a 7-Mana 6/7 Minion that reads, "Deathrattle: Summon a random friendly Beast that died this game."

Hunter Legendaries

Professor Putricide

Professor Putricide is a 4-Mana 5/4 Minion that reads, "After you play a Secret, put a random Hunter Secret into the battlefield."

Secret Hunter hasn't been a thing since before Mean Streets of Gadgetzan came out. It was great then, but this seems like a late time to put this card into play. We got one Secret, and this card in the set, but they don't seem to have an emphasis on Secrets in this expansion.

Deathstalker Rexxar

Deathstalker Rexxar is the Hunter Hero Card. It costs 6 Mana, gives you 5 Armor, and reads, "Battlecry: Deal 2 damage to all enemy minions." It also replaces your Hero Power with Built-A-Beast.

I love the flavor of Deathstalker Rexxar. His Battlecry of a 2-damage AoE is enough like the Secret Explosive Trap that it fits him nicely. What's really insane about this (and all) of the Hero Cards is the new Hero Power. Deathstalker Rexxar's is...

Build-A-Beast is Deathsalker Rexxar's new Hero Power. Build-A-Beast costs 2 Mana, and reads, "Craft a custom Zombeast."

Build-A-Beast! If the Meta is slow enough to allow Build-A-Beast to find purchase, this could be crazy! One of the rules is that it caps the amount of mana per card you can choose from at 5 (so you can't include Savannah Highmane as one of the cards -- Alas!)

Mage

Mage Commons

Breath of Sindragosa

Breath of Sindragosa is a 1-Mana Spell that reads, "Deal 2 damage to a random enemy minion and Freeze it."

1-Mana for 2 damages on an enemy minion is decent (see Arcane Blast from The Grand Tournament, which saw play). Freezing it is nice. Being so cheap combines well with Archmage Antonidas. The randomness of the target is the big drawback. I don't think this Spell will see much play. 

Coldwraith

Coldwraith is a 3-Mana 3/4 Minion that reads, "Battlecry: If an enemy is Frozen, draw a card."

Digging into your deck is nice, so if you're playing enough Freeze effects this might be played. I doubt it though. It could be a solid pick in Arena, though!

Frost Clone

Frost Clone is a 3-Mana Secret that reads, "Secret: After your opponent plays a minion, put 2 copies of it into your hand."

Opponents will play around this Secret similarly to Mirror Entity. That said, if you're able to land it on a minion with a strong Battlecry, that is where it would shine (particularly over the aforementioned Mirror Entity). I doubt this will see much play in constructed, but Mage in Arena gets another buff.

Mage Rares

Ice Walker

Ice Walker is a 2-Mana 1/3 Elemental Minion that reads, "Your Hero Power also Freezes the target."

2-Mana for a 1/3 is not ideal. Requiring another 2 Mana to ping is also not ideal.

Doomed Apprentice

Doomed Apprentice is a 3-Mana 3/2 Minion that reads, "Your Opponent's spells cost (1) more."

Cards that mess with your opponent's ability to play cards is great. What is odd to me is that this costs more than Sorcerer's Apprentice (which reduces the cost of your own spells by 1 Mana) for the same statline. I like the counterplay element of Doomed Apprentice, but I feel that it is 1 Mana too expensive. 

Ghastly Conjurer

Ghastly Conjurer is a 4-Mana 2/6 Minion that reads, "Battlecry: Add a 'Mirror Image' spell to your hand."

This is another overcosted Mage minion. Water Elemental costs the same amount of Mana, has 1 more Attack, and Freezes anything damaged by it. The Battlecry here helps the Mage Quest Open the Waygate, and gives another spell to combine with Archmage Antonidas. But the cost of the minion (while having good health) seems odd to me.

Mage Epics

Simulacrum

Simulacrum is a 3-Mana Spell that reads, "Copy the lowest Cost minion in your hand."

I like this card! I don't know how competitively viable it is, but it looks fun. This could be a great addition to the Mage Quest Open the Waygate, helping you get an additional Arcane Giant to finish off your opponent. I don't know if it will be competitively viable, but it looks like fun!

Glacial Mysteries

Glacial Mysteries is an 8-Mana Spell that reads, "Put one of each Secret from your deck into the battlefield."

This is an interesting card. The Mage Secrets being so expensive makes this cheaper if you can pull 3 or more Secrets out of your deck. It helps thin out your deck to draw into more proactive cards. But it will eat up the majority of your turn. I don't think this card is very good, but it's definitely interesting.

Mage Legendaries

Sindragosa

Sindragosa is an 8-Mana 8/8 Dragon Minion that reads, "Battlecry: Summon two 0/1 Frozen Champions."

I really like Sindragosa! Dragon Mage new class! In all seriousness, the statline is solid, and is appropriately costed. What makes this card really interesting are the Frozen Champions...

The Frozen Champion tokens read, "Deathrattle: Add a random Legendary minion to your hand."

which add a Legendary Minion to your hand when they die. I like that it adds them to your hand, so that you can play them when they would be most effective, and you don't miss out on the Battlecry (though you don't get to have the immediate pressure that you would if it placed them right on the deck).

Frost Lich Jaina

Frost Lich Jaina is the Mage Hero Card. It costs 9 Mana, gives you 5 Armor, and reads, "Battlecry: Summon a 3/6 Water Elemental. Your Elementals have Lifesteal this game." It also replaces your Hero Power with Icy Touch.

Frost Lich Jaina provides a major incentive to play Elemental Mage. Right now Elemental Mage is not a competitively viable deck, but giving Elementals Lifeteal could help this deck survive into the late game, especially because of the Hero Power Icy Touch...

Icy Touch is Frost Lich Jaina's new Hero Power. Icy Touch costs 2 Mana, and reads, "Deal 1 damage. If this kills a minion, summon a Water Elemental."

which has the possibility to create additional Water Elementals if the Hero Power kills a minion. This helps get more Freeze effects on board, as well as gaining additional Lifesteal minions on board. I hope that Elemental Mage sees play after this card is released, but I'm not sure if that will happen.

Paladin

Paladin Commons

Righteous Protector

Righteous Protector is a 1-Mana 1/1 Minion with Taunt and Divine Shield

Righteous Protector is an Argent Squire with Taunt. In a Divine Shield focused deck, it could perform very well!

Dark Conviction

Dark Conviction is a 2-Mana Spell that reads, "Set a minion's Attack and Health to 3."

Dark Conviction is great to buff your own small minions, or to make your opponent's large minions more manageable. I can see this being run in some control Paladins, but I'm not sure what would be cut for it.

Chillblade Champion

Chillblade Champion is a 4-Mana 3/2 Minion with Charge and Lifesteal

Chillblade Champion having Charge and Lifesteal are the most exciting parts of the card. It is expensive for its statline, but it also heals you up. I doubt it will see much play.

Paladin Rares

Desperate Stand

Desperate Stand is a 2-Mana Spell that reads, "Give a minion 'Deathrattle: Return this to life with 1 Health.'"

This is a more expensive, targeted Redemption, that can be silenced away. I like it! It fits the mana curve for Tirion Fordring nicely. With the amount of Divine Shield synergy for Paladin in this set, there should be no lack of good targets for Desperate Stand.

Howling Commander

Howling Commander is a 3-Mana 2/2 that reads, "Battlecry: Draw a Divine Shield minion from your deck."

Speaking of Divine Shield synergy, here's one! I love cards that draw specific types of cards out of your deck. If Divine Shield Paladin becomes a thing, this will definitely be in it.

Arrogant Crusader

Arrogant Crusader is a 4-Mana 5/2 Minion that reads, "Deathrattle: If it's your opponent's turn, summon a 2/2 Ghoul."

Arrogant Crusader has low Health for the Mana cost, but its Deathrattle could make it work well in some Midrange type decks. Being able to attack with Arrogant Crusader, either on board or to your opponent's face would be strong, and the Deathrattle incentivizes your opponent to ignore it. Vryghoul and other low-Health Deathrattle Minions could be strong in a more Aggressive N'Zoth deck, enabling them to come back even if they don't see immediate value. That said, its 5 attack may make it actually a target, while still leaving a minion on your board, albeit a small one.

Paladin Epics

Light's Sorrow

Light's Sorrow is a 4-Mana 1/4 Weapon that reads, "After a friendly minion loses Divine Shield, gain +1 Attack."

Another card that synergizes well with Divine Shield. Play Light's Sorrow, trade off a few minions with Divine Shield on deck, and instantly grow your weapon! If the deck performs well, this will almost certainly be in it.

Blackguard

Blackguard is a 6-Mana 3/9 Minion that reads, "Whenever your hero is healed, deal that much damage to a random enemy minion."

I love this card! It has a lot of health to hopefully last to the next turn. Then if your opponent plays a large minion, you can use Forbidden Healing to kill it off. This will help make Control Paladin better. Of note: if you attack with Truesilver Champion, you heal before you hit, which would make the random damage hit first.

Paladin Legendaries

Bolvar, Fireblood

Bolvar, Fireblood is a 5-Mana 1/7 Minion with Divine Shield that reads, "After a Friendly Minion loses Divine Shield, gain +2 Attack."

More Divine Shield love! This minion solidifies the fact that Blizzard is pushing the Divine Shield Paladin archetype, allowing it to utilize a Midrange style as well as the current Aggro. If the deck is good, Bolvar, Fireblood will likely be in it. If it's not, Bolvar, Fireblood will not be played.

Uther of the Ebon Blade

Uther of the Ebon Blade is the Paladin Hero Card. It Costs 9 Mana, gives you 5 Armor, and reads, "Battlecry: Equip a 5/3 Lifesteal weapon." It also replaces your Hero Power with The Four Horsemen.

Just on the face, a 9-Mana, gain 5 Armor, equip a 5/3 Weapon with Lifesteal is pretty awesome. Let's see what the Hero Power is...

The Four Horsemen is Uther of the Ebon Blade's new Hero Power. The Four Horsement costs 2 Mana and reads, "Summon a 2/2 Horseman. If you have all 4, destroy the enemy hero."

Summon a 2/2 Horseman? Yawn... wait... if you have all 4 on board, you win? That's awesome! Even if you never achieve the dream, having 2/2s with soft taunt is good, especially since they have a (small) bite to them with 2 attack. They'll struggle against any Area of Effect spells (like Blizzard, Flamestrike, Lightning Storm, etc.), but drawing removal without having to play cards to do it is valuable. Unless you get all 4 on board it's not overpowered, and it's a great upgrade to the Paladin Hero Power.

Priest

Priest Commons

Shadow Ascendant

Shadow Ascendant is a 2-Mana 2/2 Minion that reads, "At the end of your turn, give another random friendly minion +1/+1."

Your turn-1 Northshire Cleric can become a 2/4 (with more opportunity to heal), which is a good 1-2 play. But it's another 2-drop for Priest. This joins Radiant Elemental, Shadow Visions, and Shadow Word: Pain in the 2-drop slot. With Divine Spirit (if you're running a Divine Spirit/Inner Fire deck) and Purify (if you're running a Purify Priest deck), the 2-slot may be a bit too crowded for Shadow Ascendant to make the cut. It has a lot of potential though!

Spirit Lash

Spirit Lash is a 2-Mana Spell with Lifesteal that reads, "Deal 1 damage to all minions."

One card that has the potential to force its way into that 2-drop slot is Spirit Lash. It's essentially a Whirlwind for Priest... that gives you Health for each bit of damage done. It's a card I would love to get from Lyra the Sunshard (which gives you a random Priest spell in your hand for every spell you cost), and would be great by itself against token decks.

Acolyte of Agony

Acolyte of Agony is a 3-Mana 3/3 Minion with Lifesteal

With the same statline as Curious Glimmerroot, Acolyte of Agony would be a good tempo turn 3 play. Things can trade up into it, but it'll heal you for 3 in the process. I see possibility for this card, but I don't know if it will worm its way into strong decks.

Priest Rares

Eternal Servitude

Eternal Servitude is a 4-Mana Spell that reads, "Discover a friendly minion that died this game. Summon it."

I really like Eternal Servitude! Discovering a resurrected card, particularly since it plays it directly onto the board, has the possibility to be incredibly strong. It breaks even to resurrect Priest of the Feast, Shifting Shade, and Tortollan Shellraiser, and you start getting a lot of value when you resurrect Drakonid Operative (in Dragon Priest), Lyra the Sunshard, and Prophet Velen (possible OTK Priest play?). Even Injured Blademaster would be a good resurrection. I think this card has potential, even if it doesn't see competitive play.

Devour Mind

Devour Mind is a 5-Mana Spell that reads, "Copy 3 cards in your opponent's deck and add them to your hand."

Burgle Priest gets another card! It helps with card advantage, but it won't synergize with your deck. Along with Crystalline Oracle, Curious Glimmerroot, Thoughtsteal, Shifting Shade, and Drakonid Operative, you can play a lot of your opponent's cards! It'll be a fun meme deck, but I don't know if it'll be competitive.

Shadow Essence

Shadow Essence is a 6-Mana Spell that reads, "Summon a 5/5 copy of a random minion in your deck."

Shadow Essence could find its place in an Awaken the Makers/N'Zoth/Deathrattle deck, making the minion it summons gain additional value with the added Deathrattle. Acolyte of Pain would be another great summon. This card has great potential!

Priest Epics

Embrace Darkness

Embrace Darkness is a 6-Mana Spell that reads, Choose an enemy minion. At the start of your turn, gain control over it."

Embrace Darkness is a 6-Mana Mind Control that gives your opponent a chance to kill it off first. If you've got nothing on board (and are not in danger of dying), Embrace Darkness would be a great counterplay to an opponent's Deathwing.

Obsidian Statue

Obsidian Statue is a 9-Mana 4/8 Minion with Taunt and Lifesteal that reads, "Deathrattle: Destroy a random enemy minion."

Obsidian Statue is expensive, and its Deathrattle would make a much better Battlecry. But this gives your opponent a chance to play the lottery. If you've isolated a strong minion on their board, they're likely to play as many tokens as they can to try to keep it from dying. Having Taunt and Lifesteal make this card more interesting, but it may be overcosted at 9 Mana.

Priest Legendaries

Archbishop Benedictus

Archbishop Benedictus is a 7-Mana 4/6 Minion that reads, "Battlecry: Shuffle a copy of your opponent's deck into your deck." 

I'm not sure what the idea is for Archbishop Benedictus. It'll go in the aforementioned Burgle Priest deck, but having the opponent's entire deck shuffled into yours just dilutes your own draws by playing 2 different decks in the same one. If your cards focus on getting your own opponent's cards, then it'll shine in that deck. I like it for the memey Burgle Priest, but I don't think that Archbishop Benedictus will see competitive play, unless Fatigue decks start suddenly seeing a lot of play (which I think is unlikely).

Shadowreaper Anduin

Shadowreaper Anduin is the Priest Hero Card. It costs 8 Mana, gives you 5 Armor, and reads, "Battlecry: Destroy all minions with 5 or more Attack." It also replaces your Hero Power with Voidform.

I really like Shadowreaper Anduin, though I think it's too expensive. The Battlecry is powerful, particularly if long games become the meta (which I think and hope it will), by destroying all Minions with 5 or more Attack. Its Hero Power change is...

Voidform is Shadowreaper Anduin's new Hero Power. Voidform costs 2 Mana, and reads, "Deal 2 damage. After you play a card, refresh this."

Voidform! Voidform is like Shadowform, a card that doesn't see much play in the current meta. What sets Voidform apart is that whenever you play a card, you can replay your Hero Power, which has the possibility of being quite powerful. Something like this would fit more naturally in Rogue. I hope that Shadowreaper Anduin sees play in tier 1 decks, but I'm not counting on it.

Rogue

Rogue Commons

Leeching Poison

Leeching Poison is a 2-Mana Spell that reads, "Give your weapon Lifesteal."

Leeching Poison could be great, if Rogue sees more Weapons. Currently, Deadly Fork, Perdition's Blade, Obsidian Shard, and Assassin's Blade are the Weapons Rogue has access to, along with Shadowblade in this current expansion. I don't know that any of those weapons are strong enough incentive to run Leeching Poison in a Rogue deck, because healing for 2 with the Rogue Hero Power weapon is not enough.

Plague Scientist

Plague Scientist is a 3-Mana 2/3 Minion that reads, "Combo: Give a friendly minion Poisonous."

Plague Scientist is great! Giving a friendly minion Poisonous has the potential to have a Swashburglar or Patches take down even the greatest of foes.

Bone Baron

Bone Baron is a 5-Mana 5/5 that reads, "Deathrattle: Add two 1/1 Skeletons to your hand."

If these Skeletons cost 1 (which I believe that they do), then Bone Baron is great! Adding more cheaply costed minions to your hand as to activate Combo opportunities could be great to produce a big Edwin VanCleef or Questing Adventurer.

Rogue Rare Cards

Roll the Bones

Roll the Bones is a 2-Mana Spell that reads, "Draw a card. If it has Deathrattle, cast this again."

Rogue only has a handful of class Deathrattle cards in Standard, of them only Sherazin, Corpse Flower is the only run currently run in competitive decks (though Xaril, Poisoned Mind has seen competitive play in the past, and Undercity Huckster is fun in Burgle Rogue). A 2-Mana draw Spell is decent, but fairly unlikely to net more than one draw. There are some powerful Neutral Deathrattle minions, though. Could this be a harbinger of N'Zoth Rogue?

Shadowblade

Shadowblade is a 3-Mana 3/2 Weapon that reads, "Battlecry: Your hero is Immune this turn."

Shadowblade is a really promising Rogue Weapon. With the first swing not netting you damage, I can see this being run in Rogue to deal with the board without damaging your face, Particularly with healing being practically nonexistent in Rogue decks. 

Runeforge Haunter

Runeforge Haunter is a 4-Mana 5/3 Minion that reads, "During your turn, your weapon doesn't lose Durability."

I can see Runeforge Haunter finding a good home. Shadowblade and Doomerang may be enough to help Rogue run Weapons to success. Allowing you to utilize your weapon long enough to return it to your hand with Doomerang could be very beneficial!

Rogue Epics

Doomerang

Doomerang is a 1-Mana Spell that reads, "Throw your weapon at a minion. It deals its damage, then returns it to your hand."

I really like Doomerang, it makes running Weapons in Rogue worth it, because of the value it provides. Being 1 Mana also synergizes with the current Miracle Rogue strategy of using cheap Spells with Gadgetzan Auctioneer to draw through your deck quickly to reach your win condition.

Spectral Pillager

Spectral Pillager is a 6-Mana 5/5 Minion that reads, "Combo: Deal damage equal to the number of other cards you've played this turn."

You're not likely to play a ton of cards before dropping Spectral Pillager, but Rogue's Combo emphasis could help Spectral Pillager shine. I don't know if it will find a home in a deck this expansion, but I really like Spectral Pillager being a card in Rogue.

Rogue Legendaries

Lilian Voss

Lilian Voss is a 4-Mana 4/5 Minion that reads, "Battlecry: Replace spells in your hand with random spells (from your opponent's class.)"

Burgle Rogue gets more love in Lilian Voss. I don't like that it replaces your own Spells, since Rogue has some great spells (see: Backstab, Preparation, Eviscerate, Sap, Fan of Knives, and Mimic Pod, among others). Playing Lilian Voss followed by Ethereal Peddler has the possibility to be quite strong, particularly with a turn 1 Swashburglar or Hallucination, turn 2 Undercity Huckster, and Turn 3 Shaku, the Collector. Burgle Rogue will be a fun meme deck, but with the randomness in the cards you get (instead of from your opponent's deck in Burgle Priest), I don't think that Lilian Voss will push Burgle Rogue into competitive play.

Valeera the Hollow

Valeera the Hollow is the Rogue Hero Card. It costs 9 Mana, gives you 5 Armor, and reads, "Battlecry: Gain Stealth until your next turn." It also replaces your Hero Power with Death's Shadow.

At 9 Mana, Valeera the Hollow hopes to be a great late game card. Like the other Hero Cards, it gives you 5 Armor, and her individual Battlecry is to gain Stealth until the next turn, so if you plan on attacking, do it before playing Valeera the Hollow! 

Death's Shadow is Valeera the Hollow's new Hero Power. Death's Shadow is passive, and reads, "During your turn, add a 'Shadow Reflection' to your hand."

Valeera the Hollow's Hero Power of Death's Shadow is interesting. It's passive, which means that you don't have to pay a Mana cost for it, and it gives you a Shadow Reflection for each turn. You will only have 1 Shadow Reflection in your hand per turn, so holding onto a Shadow Reflection doesn't give you 2.

The Shadow Reflection card is in your hand once each turn. It reads, "Each time you play a card, transform this into a copy of it."

Shadow Reflection itself transforms itself into a copy of the last card you played. The card that was showcased on the reveal was Arcane Giant, which would be amazing. If you have held onto an Edwin VanCleef until after turn 9, you have the possibility to put 2 beefy Edwins on board. Need additional damage to finish off your opponent, or a strong minion? If you play Eviscerate before playing this card, you can play another one. I like the idea of Shadow Reflection, and I hope that it lives up to my hopes.

Shaman

Shaman Commons

Brrrloc

Brrrloc is a 2-Mana 2/2 Murloc Minion that reads, "Battlecry: Freeze an enemy."

Shaman gets a lot of Freeze effects this expansion. The first one it gets is a 2-Mana 2/2 Murloc. If Freezing Shaman takes as an archetype, Brrloc will definitely see play. If Murloc Shaman takes as an archetype, Brrrloc will likely see play as well. There are possibilities here, but it's likely dependent on what deck archetypes actually take, as it's not a particularly strong card in its own right.

Ice Fishing

Ice Fishing is a 2-Man Spell that reads, "Draw 2 Murlocs from your deck."

If Murloc Shaman takes off, Ice Fishing will be great. I mentioned earlier that I like cards that draw specific types of cards from your deck, and Ice Fishing is no exception. Like Brrrloc, if Murloc Shaman takes, then Ice Fishing will likely be an inclusion.

Drakkari Defender

Drakkari Defender is a 3-Mana 2/8 Minion with Taunt and an Overload of (3).

For a net 6 Mana, Drakkari Defender seems quite expensive. However, with Overload synergy taking a center stage with Snowfury Giant, this could see play in a Control Shaman deck.

Shaman Rares

Avalanche

Avalanche is a 4-Mana Spell that reads, "Freeze a minion and deal 3 damage to adjacent ones."

More Freezing for Shaman. If Freezing Shaman becomes a thing, then Avalanche will likely be included.

Ice Breaker

Ice Breaker is a 3-Mana 1/3 Weapon that reads, "Destroy any Frozen minion damaged by this."

If Freezing Shaman takes, Ice Breaker will likely be included. Shaman is getting some Freeze effects this expansion, but it may not be enough to negate the low amount of freeze cards in Shaman before this expansion, even in Wild.

Voodoo Hexxer

Voodoo Hexxer is a 5-Mana 2/7 Minion with Taunt that reads, "Freeze any character damaged by this minion."

Voodoo Hexxer is another card that will Freeze minions. The addition of Taunt helps make this a possibility, and could be played in a more control oriented Shaman decks, regardless if Freeze Shaman takes off. It's a little expensive, but Alley Armorsmith sees play in Warrior with different cardtext. Voodoo Hexxer has possibility.

Shaman Epics

Cryostasis

Cryostasis is a 2-Mana Spell that reads, "Give a minion +3/+3 and Freeze it."

Cryostasis gives more Freeze synergy. You will likely only use this on a friendly minion, making the Freeze itself detrimental. If only there was another card that would incentivize Freezing your own minions... (Spoiler alert: there is.)

Snowfury Giant

Snowfury Giant is an 11-Mana 8/8 Elemental Minion that reads, "Costs (1) less for each Mana Crystal you've Overloaded this game.

I really, really like Snowfury Giant. The tempo loss that Overload brings about pays off with a cheaper 8/8 Elemental.

Shaman Legendaries

Moorabi

Moorabi is a 6-Mana 4/4 Minion that reads, "Whenever another minion is Frozen, add a copy of it to your hand."

And the aforementioned incentive to Freeze your own Minions is Moorabi! If only it didn't have the "another" added in there, then Moorabi + Cryostasis would be a decent turn 9 play. At 6 Mana, its 4/4 statline is a little underwhelming, but you don't play Moorabi for the body. You play it for the effect. If Freeze Shaman is good, Moorabi will be one reason why.

Thrall, Deathseer

Thrall, Deathseer is the Shaman Hero Card. It costs 5 Mana, gives you 5 Armor, and reads, "Battlecry: Transform your minions into random ones that cost (2) more." It also replaces your Hero Power with Transmute Spirit.

I love this card! Turn 10 Dopplegangster into Thrall, Deathseer would be ridiculous. I love the Evolve mechanic, and Thrall, Deathseer evolving your board by 2 for 5 Mana is great flavor. Like all other Hero Cards, it also comes with 5 Armor and a new Hero Power, which is...

Transmute Spirit is Trall, Deathseeker's new Hero Power. Death's Shadow reads, "Transform a friendly minion into a random one that costs (1) more."

Transmute Spirit gives you a 2-Mana evolve one Minion. This addition will help keep Shaman's board growing bigger and bigger, allowing them to make efficient trades that almost kill its minions, then evolve it to a fresh minion that costs 1 Mana more. I like this card, and hope it sees competitive play.

Warlock

Warlock Commons

Sanguine Reveler

Sanguine Reveler is a 1-Mana 1/1 Minion that reads, "Battlecry: Destroy a friendly minion and gain +2/+2.

Warlock has some precedence for destroying friendly Minions for its own advantage, like with Shadowflame (to take down your opponent's board) and Ravenous Pterrordax (to Adapt twice). I think that a 1-Mana 1/1, which only gets the benefit of gaining +2/+2 for destroying one of your own minions is a little too weak.

Drain Soul

Drain Soul is a 2-Mana Spell with Lifesteal that reads, "Deal 2 damage to a minion."

Drain Soul is a great Spell to add to Warlock's repertoire. It synergizes well with any Spell Damage +x effects by not only granting additional damage, but also granting additional healing. If a Control-oriented Warlock deck sees play Drain Soul will probably be in it, particularly if it has a Demon focus, where it can include Street Trickster for Demon and Spell Damage synergies.

Wailing Felhound

Wailing Felhound is a 3-Mana 3/6 Demon Minion that reads, "Whenever this minion takes damage, discard a random card."

What is the benefit of this card? It has a lot of health, which seems to only be beneficial for your opponent, as discarding that many cards is very detrimental, unless your hand is solely comprised of Clutchmother Zavas and Silverware Golem, particularly with a Malchezaar's Imp on board, and the Warlock Quest Lakkari Sacrifice active. It's not going to happen, but it's one of the few times that Wailing Felhound would be intentionally played. Wailing Felhound seems like a nerf to Kabal Trafficker (a 6-Mana 6/6 that adds a random Demon to your hand at the end of your turn), which is a strong card, but not one that has proved problematic.

All that said, Treachery and Wailing Felhound may be the intent. Having a wide board against an opponent and playing Wailing Felhound and Treachery on it could be great to make your opponent discard their hand. Extra points if you can count to 6 with Defile (mentioned later).

Warlock Rares

Defile

Defile is a 2-Mana Spell that reads, "Deal 1 damage to all minions. If any die, cast this again."

Defile will be a great card against token decks or damaged boards. If the board has Minions with 1, 2, 3, 4, etc. remaining Health, then Defile will be amazing.

Unwilling Sacrifice

Unwilling Sacrifice is a 3-Mana Spell that reads, "Choose a friendly minion. Destroy it and a random enemy minion."

Did you get a Wailing Felhound from your Kabal Trafficker? On turn 6, play it and Unwilling Sacrifice to destroy a random enemy Minion. Isolate a big Minion on your opponent's board to ensure that you destroy the right one for maximum value.

Despicable Dreadlord

Despicable Dreadlord is a 5-Mana 4/5 Demon Minion that reads, "At the end of your turn, deal 1 damage to all enemy minions."

Being a Demon helps Despicable Dreadlord. If a Midrange Warlock deck comes out. A 4/5 body is decent, and dealing 1 damage to all enemy Minions at the end of each turn is particularly strong against Token decks.

Warlock Epics

Gnomeferatu

Gnomeferatu is a 2-Mana 2/3 Minion that reads, "Battlecry: Remove the top card of your opponent's deck."

I really like Gnomeferratu. It's great to play at any time. The stats are reasonable, and messing with your opponent's hand or deck has a soft spot in my heart. If Gnomeferratu had a Demon tag, then it would be perfect. Not having the Demon tag makes more sense for the flavor of the card, though.

Treachery

Treachery is a 3-Mana Spell that reads, Choose a friendly minion and give it to your opponent."

The only cards that I can see this working with are Wailing Felhound, Tickling Abomination, and Bomb Squad. Playing them together makes 2 terrible cards great. Just don't have your synergizing minions pulled out by a Dirty Rat, or your Treachery nullified by Counterspell!

Warlock Legendaries

Blood-Queen Lana'thel

Blood-Queen Lana'thel is a 5-Mana 1/6 Minion with Lifesteal that reads, "Has +1 Attack for each card you've discarded this game."

Discard Warlock gets another incentive with Blood-Queen Lana'thel. The biggest downside is that you can discard Blood-Queen Lana'thel while trying to buff her. I hope that discard Warlock becomes great again (my highest rank was attained with discard Zoolock), but I don't think that it'll happen this expansion.

Bloodreaver Gul'dan

Bloodreaver Gul'dan is the Warlock Hero Card. It costs 10 Mana, gives you 5 Armor, and reads, "Battlecry: Summon all friendly Demons that died this game."
Siphon Life is Bloodreaver Gul'dan's new Hero Power. Siphon Life costs 2 mana, has Lifesteal, and reads, "Deal 3 damage."

I may be seeing Bloodreaver Gul'dan with controlled, demonic tinted glasses, but I am so excited to play with this card. Bloodreaver Gul'dan is expensive, but his effect is worth it. The Battlecry is like N'Zoth type effect for the Demon tribe, which is powerful in and of itself. Changing the Hero Power from digging further into your deck to dealing damage and healing your Hero helps you control the board and survive into the late game.

Warrior

Warrior Commons

Animated Berserker

Animated Berserker is a 1-Mana 1/3 Minion that reads, "After you play a minion, deal 1 damage to it."

A lot of Warrior cards synergize really well with having pings on them. Animated Berserker helps attain just that! It's aided by being a 1/3 in the 1 Mana slot, which makes it a strong turn 2 play, even with no synergies in hand.

Forge of Souls

Forge of Souls is a 2-Mana Spell that reads, "Draw 2 weapons from your deck."

Drawing 2 Weapons from your deck is decent, but since you can only play one Weapon at a time it isn't as impactful. Forge of Souls may be a slight buff to Hobart Grapplehammer. I can see Pirate Warrior playing this.

Blood Razor

Blood Razor is a 4-Mana 2/2 Weapon that reads, "Battlecry and Deathrattle: Deal 1 damage to all minions."

Blood Razor is a Death's Bite for Standard. It has 2 less attack than Death's Bite, but has an added Whirlwind effect as the Battlecry along with the Deathrattle.

Warrior Rares

Mountainfire Armor

Mountainfire Armor is a 3-Mana 4/3 Minion that reads, "Deathrattle: If it's your opponent's turn, gain 6 Armor."

Mountainfire Armor will likely be ignored by your opponent, which helps its overstatted body either trade up, or hit face for maximum damage. If they decide to take care of it, you get 6 Armor for 3 Mana, as well as a removal spell or forcing them to trade on board. I like this card for Midrange style Warrior play.

Val'kyr Soulclaimer

Val'kyr Soulclaimer is a 3-Mana 1/4 Minion that reads, "Whenever this minion survives damages, summon a 2/2 Ghoul."

Val'kyr Soulclaimer works really well with the ping or Whirlwind effects prolific in Warrior, and added to with Animated Berserker. These cards help push a more Midrange style Warrior deck.

Death Revenant

Death Revenant is a 5-Mana 3/3 Minion that reads, "Battlecry: Gain +1/+1 for each damaged minion."

With all the Whirlwind effects that Warrior has, Death Revenant has the possibility to be a quite large minion. If there are 2 damaged Minions on board, Death Revenant breaks even on its stats, which should be easy to do on curve. With 5 damaged Minions on board, it is a 5-Mana 8/8, which is absurd.

Warrior Epics

Bring It On!

Bring It On! is a 2-Mana Spell that reads, "Gain 10 Armor. Reduce the Cost of minions in your opponent's hand by (2)."

Gaining 10 Armor for 2 Mana is great! The drawback of reducing your opponent's Minions in hand by 2 Mana is the real drawback. If Fatigue Warrior becomes a thing, this could be a great card, particularly to bait your opponent to overcommitting to the board before a Brawl turn.

Dead Man's Hand

Dead Man's Hand is a 2-Mana Spell that reads, "Shuffle a copy of your hand into your deck."

Again, if Fatigue Warrior becomes a thing, Dead Man's Hand will be good. You could get an additional win condition by putting another Grommash Hellscream into your deck, or try to go infinite with another Dead Man's Hand in hand while your opponent Fatigues. I doubt that this card will see play, though.

Warrior Legendaries

Rotface

Rotface is an 8-Mana Minion that reads, "Whenever this minion survives damage, summon a random Legendary minion."

Rotface is another card that benefits from the ping and Whirlwind effects that Warrior utilizes. This could be a great card in a Midrange Warrior deck. I hope Midrange Warrior becomes a great class!

Scourgelord Garrosh

Scourgelord Garrosh is the Warrior Hero Card. It costs 8 Mana, gives you 5 Armor, and reads, "Battlecry: Equip a 4/3 Shadowmourne that also damages adjacent minions."
Bladestorm is Scourgelord Garrosh's new Hero Power. Bladestorm costs 2 Mana and reads, "Deal 1 damage to all minions."

If a Midrange Warrior that focuses on pinging your own minions is successful, then Scourgelord Garrosh will be the reason why. The Battlecry that gives you a 4/3 Weapon that damages multiple minions on board helps the Warrior fight for board even more effectively, and the at-will Whirlwind Effect from the Hero Power enables these buffs to happen at will. Scourgelord Garrosh will hopefully help push this Midrange Warrior to success.

Neutral

Neutral Commons

Snowflipper Penguin

Snlowflipper Penguin is a 0-Mana 1/1 Beast Minion

Snowflipper Penguin is cute! And a Beast!

Acherus Veteran

Acherus Veteran is a 1-Mana 2/1 Minion that reads, "Battlecry: Give a friendly minion +1 Attack."

Acherus Veteran is a good 1-Mana 1 Attack buff to another minion, while still leaving a body on board. It's susceptible to even the smallest Area of Effect card, but if you're playing Acherus Veteran, it's likely for the Battlecry.

Deadscale Knight

Deadscale Knight is a 1-Mana 1/1 Murloc Minion with Lifesteal

Deadscale Knight could be good in a Murloc deck, and is a big buff to the Shaman Quest Unite the Murlocs and the Shaman Spell Maelstrom Portal.

Wretched Tiller

Wretched Tiller is a 1-Mana 1/1 Minion that reads, "Whenever this minion attacks, deal 2 damage to the enemy hero."

Wretched Tiller is a good card to play in an Aggressive or Zoo style deck, but its small body will likely render its cardtext negligible without buffs. At least it could draw removal, even if it's just the 2 Mana of a Hero Power, slowing your opponent down at the cost of 1 card.

Fallen Sun Cleric

Fallen Sun Cleric is a 2-Mana 2/1 Minion that reads, "Battlecry: Give a friendly minion +1/+1."

Fallen Sun Cleric's body is underwhelming, but a 2-Mana card giving a friendly Minion +1/+1, and leaving a (small) body on board could be decent in Arena.

Tainted Zealot

Tainted Zealot is a 2-Mana 1/1 Minion with Divine Shield and Spell Damage +1.

Having the same cost and Spell Damage +1 effect of Bloodmage Thalnos, but with Divine Shield rather than the Deathrattle of drawing a card, Tainted Zealot is more likely to stick on board to provide the Spell Damage +1 effect, but doesn't have the benefit of drawing you a card. It's decent, particularly in decks that thrive on strong Spells.

Tuskarr Fisherman

Tuskarr Fisherman is a 2-Mana 2/3 Minion that reads, "Battlecry: Give a friendly minion Spell Damage +1."

Needing to have another Minion on board is detrimental, and the 2/3 body is bland for a 2 Mana Minion. I don't see Tuskarr Fisherman seeing play, since Tainted Zealot and Bloodmage Thalnos are strictly less situational.

Deathspeaker

Deathspeaker is a 3-Mana 2/4 Minion that reads, "Battlecry: Give a friendly minion Immune this turn."

Deathspeaker is interesting! Giving a friendly Minion Immune for a turn is valuable, and the body for the Mana cost is decent. I don't know if it will see play in Constructed, but it will be a great card to trade up in Arena.

Hyldnir Frostrider

Hyldnir Frostrider is a 3-Mana 4/4 Minion that reads, "Battlecry: Freeze your other minions."

Playing Hyldnir Frostrider on an empty board could be strong, but it's not likely This could be a good card in Arena.

Vryghoul

Vryghoul is a 3-Mana 3/1 Minion that reads, "Deathrattle: If it's your opponent's turn, summon a 2/2 Ghoul."

Vryghoul has a weak body for the Mana cost, but its Deathrattle could make it work well in some Midrange type decks. Being able to attack with Vryghoul, either on board or to your opponent's face would be strong, and the Deathrattle incentivizes your opponent to ignore it. Vryghoul and other low-Health Deathrattle Minions could be strong in a more Aggressive N'Zoth deck, enabling them to come back even if they don't see immediate value. 

Grave Shambler

Grave Shambler is a 4-Mana 4/4 Elemental Minion that reads, "Whenever your weapon is destroyed, gain +1/+1."

Grave Shambler could synergize well in an Elemental Shaman with Jade Claws. I don't see it being run in Constructed, but it could be fairly easy to see value and play in Arena.

Grim Necromancer

Grim Necromancer is a 4-Mana 2/4 Minion that reads, "Battlecry: Summon two 1/1 Skeletons."

4 Mana for 4/6 worth of stats is decently strong, and could work well in some Token style decks. If these decks see success, then Grim Necromancer might be a card in them. Odds are, it's a card for Arena.

Night Howler

Night Howler is a 4-Mana 3/4 Minion that reads, "Whenever this minion takes damage, gain +2 Attack."

Night Howler could see play in a Midrange Warrior deck that focuses on small amounts of damage to your own minions. It's not particularly exciting, but it could work well.

Wicked Skeleton

Wicked Skeleton is a 4-Mana 1/1 that reads, "Battlecry: Gain +1/+1 for each minion that died this turn."

3 Minions would need to die during your turn before playing Wicked Skeleton to make it have decent vanilla stats. I don't think Wicked Skeleton will see much play, which is a shame because its art is amazing.

Bloodworm

Bloodworm is a 5-Mana 4/4 Beast Minion with Lifesteal.

A little underwhelming on its face, Bloodworm is a big buff to the Build-A-Beast Hero Power from the Hunter Hero Card Deathstalker Rexxar, due to its Beast tag. If Beast Hunter sees play, it may even be included in the deck. Maybe not, too.

Cobalt Scalebane

Cobalt Scalebane is a 5-Mana 5/5 Dragon Minion that reads, "At the end of your turn, give another random friendly minion +3 Attack."

A 5-Mana 5/5 is a decent Mana to statline, it being a Dragon also helps, but what is most enticing about this card is giving another friendly minion +3 Attack and drawing removal and trades onto it instead of your other Minions that you may value more. I can see Cobalt Scalebane being played in Dragon decks.

Skelemancer

Skelemancer is a 5-Mana 2/2 Minion that reads, "Deathrattle: If it's your opponent's turn, summon an 8/8 Skeleton."

Skelemancerhas a weak body for the Mana cost, but its Deathrattle could make it work well in some Midrange type decks. Being able to attack with Vryghoul, either on board or to your opponent's face would be strong, and the Deathrattle incentivizes your opponent to ignore it. Skelemancer and other low-Health Deathrattle Minions could be strong in a more Aggressive N'Zoth deck, enabling them to come back even if they don't see immediate value.

Sunborne Val'kyr

Sunborne Val'kyr is a 5-Mana 5/4 Minion that reads, "Battlecry: Give adjacent minions +2 Health."

Board position matters with Sunborne Val'kyr! She could be good in a Midrange deck to help your minions trade up more efficiently, or weather the storm from Area of Effect cards. With no tribe tags, there are few Constructed decks that would want to play it (maybe Midrange Warrior?), but it will be great in Arena.

Venomancer

Venomancer is a 5-Mana 2/5 Minion with Poisonous

Venomancer is fairly expensive for its Attack... but its attack doesn't matter with Poisonous! 5 Health could see Venomancer actually survive an attack, but being 5 Mana leaves it vulnerable to single target removal such as Fireball or Firelands Portal. Venomancer could bait removal for bigger drops later in the game.

Necrotic Geist

Necrotic Geist is a 6-Mana 5/3 Minion that reads, "Whenever one of your other minions dies, summon a 2/2 Ghoul."

Token generation! If Token decks continue to take off, then Necrotic Geist could see play in them. It's a bit expensive for a small amount of Health, but it's meant to be played with a lot of cheap minions on board ready to attack into your opponent's board that turn and draw removal.

Spellweaver

Spellweaver is a 6-Mana 4/4 Minion with Spell Damage +2.

Spell Damage is valuable, but Spellweaver's 6 Mana for such a weak body is... not good. This is either a buff or a nerf to Moonglade Portal (buff with Spells in hand and enough Mana left over to use them, like Swipe, Wrath, etc).

Bonemare

Bonemare is a 7-Mana 4/5 minion that reads, "Battlecry: Give a friendly minion +4/+4 and Taunt."

Bonemare is interesting. It initially seems understatted having a 5/5 body for 7 Mana, but adding +4/+4 to another Minion (theoretically that can attack that turn) makes it more interesting. Bonemare could possibly see play in a Midrange deck, and would be great in Arena, if a little expensive.

Neutral Rares

Happy Ghoul

Happy Ghoul is a 3-Mana 3/3 Minion that reads, "Costs (0) if your hero was healed this turn.

Paladin and Priest are the 2 decks that are best known for healing. Being able to play a 3/3 body for free if you've healed is beneficial. I can see this used alongside Forbidden Healing, which uses all your Mana and heals depending on how much Mana you have remaining. This could enable you to use Forbidden Healing for maximum value, and still put a 3/3 body on board. I don't think this will be played in any competitive decks, but I hope I'm wrong.

Keening Banshee

Keening Banshee is a 4-Mana 5/5 that reads, "Whenever you play a card, remove the top 3 cards of your deck."

Keening Banshee is a card that your opponent will likely ignore on board, allowing him to trade up. The downside is pretty huge though, keeping you from playing many cards lest you mill your whole deck. Not a big fan. Could be good in Arena for the overstatted body being able to trade effectively on board.

Mindbreaker

Mindbreaker is a 3-Mana 2/5 Minion that reads, "Hero Powers are disabled."

Mindbreaker is really interesting, particularly with the Hero Cards in play. With 5 Health and 3 Mana, it's got a good chance to live for a turn (unless it's dead on board, or will draw removal from hand, which would also be valuable to do with a 3-Mana card).

Shallow Gravedigger

Shallow Gravedigger is a 3-Mana 3/1 Minion that reads, "Deathrattle: Add a random Deathrattle minion to your hand."

Shallow Gravedigger is interesting. It's like a more expensive Journey Below with no Discover incentive. It could be great in a N'Zoth/Deathrattle deck, and it will likely be able to trade into opponent's minions since the opponent might not want to kill it off. That said, with only one health, it would be very easy for them to prevent you from trading up. I'm quite torn about this card.

Phantom Freebooter

Phantom Freebooter is a 4-Mana 3/3 Pirate Minion that reads, "Battlecry: Gain stats equal to your weapon's."

A Pirate that synergizes with Weapons. Where have we seen this before? I can see Phantom Freebooter being played in a Pirate Warrior, but don't know if it's strong enough for the Mana cost to be effective.

Saronite Chain Gang

Saronite Chain Gang is a 4-Mana 2/3 Minion with Taunt that reads, "Battlecry: Summon a copy of this minion."

Saronite Chain Gang could be powerful in a handbuff style deck, but it most likely won't see much Constructed play. It could be great in Arena, producing two 2/3 Minions with 4 Mana.

Ticking Abomination

Ticking Abomination is a 4-Mana 5/6 Minion that reads, "Deathrattle: Deal 5 damage to your minions."

Tickling Abomination is another card that synergizes well with the Warlock card Treachery. It could find a place in a Warlock deck that runs both, but otherwise is underwhelming.

Corpse Raiser

Corpse Raiser is a 5-Mana 3/3 Minion that reads, "Battlecry: Give a friendly Minion 'Deathrattle: Resummon this minion."

If you can land Corpse Raiser onto a powerful Minion, it is well worth the Mana cost. Creating sticky minions is great for Midrange strategies, and Corpse Raiser should be great in Arena.

Bone Drake

Bone Drake is a 6-Mana 6/5 Dragon Minion that reads, "Deathrattle: Add a random Dragon to your hand."

Bone Drake will likely be played in most Dragon decks. Having 5 Health is a bit weaker than you would hope from a 6-Mana card, but the Deathrattle makes it worth it in my opinion.

Neutral Epics

Drakkari Enchanter

Drakkari Enchanter is a 3-Mana 1/5 Minion that reads, "Your end of turn effects trigger twice."

Drakkari Enchanter is a valuable card to combine with cards that have effects that trigger at the end of your turn, like Kabal Courrier, The Lich King, and Ysera. Without these cards, playing a 1/5 minion for 3 Mana is not good. The situational nature of Drakkari Enchanter.

Corpsetaker

Corpsetaker is a 4-Mana 3/3 Minion that reads, "Battlecry: Gain Taunt if your deck has a Taunt minion. Repeat for Divine Shield, Lifesteal, Windfury."

Corpsetaker could be really good in the right kind of deck. I can see it working really well in a Divine Shield Paladin deck, which will almost certainly be running Divine Shield and Taunt naturally, and could incentivize the deck to play Chillblade Champion as well for Lifesteal. Windfury is a bit of a stretch for Divine Shield Paladin, though a Young Dragonhawk could be added for Corpsetaker to take advantage of Windfury, and be a good combo with Steward of Darkshire as well.

Deathaxe Punisher

Deathaxe Punisher is a 4-Mana 2/3 Minion that reads, "Battlecry: Give a random Lifesteal minion in your hand +2/+2."

Deathaxe Punisher could be valuable in decks that play a lot of Lifesteal mechanics, but Midrange will need to be very strong in order for this sort of hand-buffing mechanic to be worth the small body for the Mana cost.

Meat Wagon

Meat Wagon is a 4-Mana 1/4 Mech Minion that reads, "Deathrattle: Summon a minion from your deck with less Attack than this minion."

Meat Wagon, it's a bit of a meme (quoth I of J4CKIECHAN). It could work well in an Egg Druid style deck that focuses on buffing your own minions (pulling larger minions) and smaller minions that build to overwhelm the opponent. I don't think that this will see much competitive play, though.

Rattling Rascal

Rattling Rascal is a 4-Mana 2/2 Minion that reads, "Battlecry: Summon a 5/5 Skeleton. Deathrattle: Summon a 5/5 Skeleton for your opponent."

Rattling Rascal is interesting, and may be played in an Egg Druid type of deck as well, to keep it from dying as easily (though it's a bit expensive for that kind of deck), or in a Handbuff Paladin type of deck. It incentivizes your opponent to kill it off to get their own 5/5 as well. To be honest, I doubt this will see play even in the decks mentioned above.

Tomb Lurker

Tomb Lurker is a 5-Mana 5/3 Minion that reads, "Battlecry: Add a random Deathrattle minion that died this game to your hand."

I really like Tomb Lurker for Deathrattle decks. The fact that its effect is a Battlecry is also good in my opinion, because then N'Zoth won't bring a 3-Health Minion back when it is played. It may be a bit expensive at 5 Mana, but the fact that it's fairly predictable in what you will get (since it's only your own Deathrattle Minions that have already died), it may well be worth the Mana cost.

Furnacefire Colossus

Furnaceface Colossus is a 6-Mana 6/6 Minion that reads, "Battlecry: Discard all weapons from your hand and gain their stats."

Furnacefire Colossus's statline is appropriate for the Mana cost, so even if it gets no value it is worth playing for tempo. What makes Furnacefire Colossus worth playing in a deck is when you would be playing Weapons alongside him.

Nerubian Unraveler

Nerubian Unraveler is a 6-Mana 5/5 Minion that reads, "Spells cost (2) more."

I love this card! Like Loatheb before it, it makes spells more costly, but Nerubian Unraveler costs one more Mana, and also causes your own spells to increase in price. Nerubian Unraveler will be a priority Minion for your opponent to kill. I can see it being played in more Midrange style decks.

Skulking Geist

Skulking Geist is a 6-Mana Minion that reads, "Battlecry: Destroy all 1-Cost spells in both hands and decks."

This kills the Jade Druid. One of the most played decks in Standard, Jade Druid has some counterplay here in Skulking Geist. If Jade Druid continues to run amok, a Skulking Geist tech will keep their Jade Idols from going infinite. If Jade Druid does not continue to be played with the Knights of the Frozen Throne expansion, then I doubt that Skulking Geist will see much play.

Neutral Legendaries

Prince Keleseth

Prince Keleseth is a 2-Mana 2/2 Minion that reads, "Battlecry: If your deck has no 2-Cost cards, give all minions in your deck +1/+1."

I like the idea of the Prince cards, but I don't think that their benefit outweighs their cost. Prince Keleseth probably has the biggest benefit, giving all of the minions in your deck +1/+1, like Mistcaller, the Shaman Legendary from The Grand Tournament. Mistcaller didn't see much play, but Shaman didn't have a big Midrange deck that relied on cards from hand, and 6 Mana was a long way into the game for such an effect. Prince Keleseth could see some play in a Midrange deck that doesn't want to play much of anything in the 2 slot, but I can't think of what that could be.

Prince Taldaram

Prince Taldaram is a 3-Mana 3/3 Minion that reads, "Battlecry: If your deck has no 3-Cost cards, transform into a 3/3 copy of a minion."

Prince Taldaram is one of the most underwhelming Princes. His cost of not playing another 3 cost card is high, and the only benefit is being able to transform into a copy of another Minion... and retain the 3/3 statline.

Arfus

Arfus is a 4-Mana 2/2 Beast Minion that reads, "Deathrattle: Add a random Death Knight card to your hand."

 Arfus is adorable! And a Beast! And holding a severed hand! Let's just focus on the body before going into the Death Knight cards, which are insanely powerful. Arfus himself costs 4 Mana, which is expensive for a 2/2 body, even for the Beast tag. The Death Knight card is given from a Deathrattle, which is both a positive and a negative. On the positive side, a Priest can steal the Death Knight card by using Potion of Madness to get the Deathrattle, on the other hand Arfus can be brought back by N'Zoth the Corruptor.

The Death Knight cards possible to get from Arfus's Deathrattle

To go down the line...

• Frostmourne is a 7-Mana 5/3 Weapon that reads, "Deathrattle: Summon every minion killed by this weapon."
• This could be quite powerful, with the downside that you would need to facetank any and all damage taken to achieve its powerful Deathrattle. Frostmourne is most powerful against minions like other Arfuses, or other minions with low attack and a powerful Deathrattle. 
• Army of the Dead is a 6-Mana Spell that reads, "Remove the top 5 cards of your deck. Summon any minions removed.
• Army of the Dead is strong in Midrange decks that do not run many spells. Since Arfus's Death Knight card is random, this one is a bit of a gamble. It has the potential to be powerful, but also has a huge drawback.
• Doom Pact is a 5-Mana Spell that reads, "Destroy all minions. Remove the top card from your deck for each minion destroyed."
• Doom Pact is an incredibly strong board clear with a big drawback. While you have the possibility of removing your win condition, you can also take away lethal damage from the board. 
• Death Grip is a 2-Mana Spell that reads, "Steal a minion from your opponent's deck and add it to your hand."
• Death Grip is one of my favorite Death Knight card. I like stealing your opponent's cards, even though it will not necessarily fit in with your strategy. 
• Death Coil is a 2-Mana Spell that reads, "Deal 5 damage to an enemy, or restore 5 Health to a friendly character."
• Death Coil is another one of my favorite Death Knight cards, because it is so flexible. If you need that last bit of damage to destroy a strong Minion or to finish off your opponent, or if you need to heal one of your own Minions or face out of lethal range, Death Coil allows you to do either one. 
• Obliterate is a 2-Mana Spell that reads, "Destroy a minion. Your hero takes damage qual to its Health."
• Obliterate is a strong card. I like that you take the damage of the Health rather than the Attack. This makes it a bitter pill to swallow against a Ysera, but allows you the flexibility of trading in as much of your board to take as much or little damage as you are comfortable with. Your hero's Health is a resource, and Obliterate enables you to use that to fight for the board. 
• Anti-Magic Shell is a 2-Mana Spell that reads "Give your minions +2/+2 and 'Can't be targeted by spells or Hero Powers.'"
• 2 Mana to buff your board in raw stats, and make them impervious to single target removal? This card is great!
• Death and Decay is a 3-Mana Spell that reads, "Deal 3 damage to all enemies."
• Death and Decay is a great Area of Effect spell that also hits your opponent's face. There's not really a drawback to this card. It's great.

All in all, the Death Knight cards are very powerful, and well worth the extra Mana cost to not fall behind from Arfus's overcosted body.

Prince Valanar

Prince Valanar is a 4-Mana 4/4 Minion that reads, "Battlecry: If your deck has no 4-Cost cards, gain Lifesteal and Taunt."

Prince Valanar is another underwhelming Prince. Again, the cost of not playing another x-cost card (in this case 4), gives an underwhelming benefit, this time granting Lifesteal and Taunt. While the effect is good, playing another 4-cost card in your deck is better.

The Lich King

The Lich King is an 8-Mana 8/8 Minion with Taunt that reads, "At the end of your turn, add a random Death Knight card to your hand."

For a full look into the Death Knight cards, see my breakdown of them with Arfus (above). The Lich King has a solid statline, at 8/8 with Taunt for 8 Mana, but where it really shines is the cardtext. The Death Knight cards are fantastic, and getting a guaranteed card at the end of your turn (barring any Secrets like Potion of Polymorph) is amazing. The Lich King will see play in most any slower deck. Of note, Drakkari Enchanter synergizes incredibly well with The Lich King, enabling you to get two Death Knight cards per turn that they both live on the board.