Hearthpwn

So "Silence a friendly minion" is roughly equal in value to "Give a minion divine shield". Good to know.

I can't wait until a paladin gets their hand on a random Purify then plays this card.

I'd say if you want an early-game defensive taunt that isn't good at attacking, Tar Creeper already fills that niche. 1 mana cheaper for 1 less health, and getting your taunts out early is very important against current aggro decks.

It's +1 health over Sen'jin Shieldmasta, in exchange for its drawback. This would normally be good imo (there are plenty decks that don't care about early-game damage) but we've been spoiled by Tar Creeper, which has a similar drawback of not being good at attacking... I don't think this will see play as long as Tar Creeper is an option.

If this was in any other class than the one that both already has access to good one-sided aoes like Blizzard and Flamestrike and has plenty of incredible cheap spells like Primordial Glyph, Frostbolt, Arcane Intellect, and all sorts of secrets...

It's a good card if it was available to non-mages, but I can't see wanting to build your mage deck around this card, and I can't see wanting to run this card if you can't rely on it being at least a 4 damage aoe either. Seems bad.

The best thing about this card is its ability to bypass drawbacks. Lakkari Felhound and Doomguard love getting summoned for free. Also, unlike the old Voidcaller, it summons from your deck, not your hand, so its like having draw a card tacked onto that card.

On the downside, it is expensive and slow, a 2/2 body isn't much of a threat on its own, unlike voidcaller's 3/4 body, and deathrattle is prone to being silenced or activated at a time of the opponent's choosing. It also prevents you from running the really good cheap demons this set added, as you don't want to spend 5 mana on a 2/2 body that summons a 1-or-2-drop.

Sacrifice 1 stat for usually 4+ armor? Sounds good. Shieldmaiden was a card that sacrificed 3 stats for 5 armor, and it saw play. Granted, against an empty or almost empty board, this card is bad, but if you're control warrior vs an enemy without a board, you're usually pretty happy anyway.

So we have:

Shieldmaiden (very good)
Holy Fire (okay)
Arcanite Reaper + Iron Hide in one card (okay)
Very Expensive Greater Healing Potion (terrible)

Could see play in the right meta, but I doubt it.

Another "nerf" to evolve shaman.

Unless I'm missing something, this is a much worse Ice Block? Ice Block can save you from fatal damage no matter what your health. With this card, if the you're at 10 and the opponent Pyroblasts you, you're dead and the secret did nothing.

It's a 2 mana semi-heal that doesn't effect the board state and is easy to play around. That's not a great secret. Ice Block is a guaranteed "You live another turn" that there's not much you can do to play around. Nothing like each other.

1) Turn 1 Pirate (Summon patches) 
2) Coin
3) Cast this on patches, get sorcerer's apprentice
4) This spell is now free. Evolve other pirate into a Deathwing
5) Laugh at your opponent, then let them take their turn 2.

So slow. The turn you play it nothing happens. The next turn the demon is summoned, and cannot attack because it was just summoned.

Best case is if you can arrange a doomguard to be summoned, since that negates its drawback, and it has charge. But even then you're just playing 5 mana for a 5/7 that can't attack till next turn for two cards. Not exactly game-breaking.

This is only good when you are constantly summonning a stream of demons for free that you wouldn't have the mana to play normally, gaining a lot of tempo... of course, you only gain this tempo after spending your turn 5 doing nothing... and you have to stack your deck with demons that you're gonna have trouble playing if you don't draw this one-of weapon.

Bleh. It isn't useless, but I can't see this actually being good.

Hah, I swear they're nerfing evolve intentionally now by printing more and more awful things to evolve into at high costs. Ironically, this just means devolve is getting stronger and stronger

The worst possible result at:
0 mana = 1/1
1 mana = 0/1
2 mana = 1/1 (or 4/5 can't attack, or Doomsayer, or Lorewalker Cho)
3 mana = 1/1
4 mana = 1/1
5 mana = 2/2 Deathrattle: Deal 5 damage to self
6 mana = 1/1
7 mana = 1/1 (new!)
8 mana = 5/4
9 mana = 5/4 Randomize everything 
10 mana = 7/5

Other new cards in Kobolds and Catacombs that aren't the worst of their cost, but are pretty bad:
5 mana = 2/4
7 mana = 3/3
8 mana = 3/5 taunt OR 4/7 OR 5/5 
9 mana = 3/8 taunt

So much worse than hungry dragon. It gives your opponent 2 mana crystals worth of tempo instead of hungry dragon's 1 mana crystal of tempo, and the mana is used to play cards they put in their deck instead of some random minion that is often almost worthless. 

To be fair, it has the upside of it being deathrattle instead of battlecry, so depending on how things go, they might not ever get the coins, but I wouldn't count on that. It's just +1/+1 over a yeti. It's no 7/7 that's for sure.

Well, on one hand, this is the most unreliable disruption ever, and at 8 mana too. If they swap back right away, all you've done is given your opponent one card from your deck in exchange for making them skip drawing a card from their deck. Once swapped back, you're two cards closer to fatigue.

On the other hand, if the opponent does want to swap back, you've essentially got a 5/5 for 3 mana (with 5 mana spent to cancel out your opponent's 5 mana) Still not worth it though.