This is probably the worst evolve cards in Hearthstone. Being able to evolve twice doesn't justify the unreasonably high cost.

This will be good if you care about stealth, otherwise I think this will be outclassed by better 1 drops such as Pharaoh Cat, Blazing Battlemage or maybe even Secretkeeper if your deck has enough secrets in it.

2 mana draw 2 is good, this will be played. You don't even have to care about secrets for this to be good.

I don't know, it just seems too slow to be worth playing. 7 mana for 7 damage next turn just isn't good enough. At this point in the game you don't want to be playing "good stats" you want to end the game. It just isn't worth it to spend your whole turn playing a single minion when it doesn't have any proactive keywords like battlecry or rush.

This card will be very annoying to play against. Getting a cheaper, better Sap with a body attached is amazing. 5 star card.

This will help fix one of Stealth minions biggest weaknesses, they have low health. Giving them immune will help keep your board alive after the smoke has cleared. This card will surely play a big part in making stealth rogue viable.

This may also be enough to make Worgen Infiltrator viable . . .

I just don't think a 2 mana Emperor Cobra is good enough to make the cut. I don't think this is bad, but it isn't better than some other secrets you would rather play instead.

Not bad. If your deck cares about playing lots of spells than this is fine, otherwise it isn't worth playing.

I just don't think this does enough to be worth playing. If you don't get it on turn 1 then it is just too slow for not enough benefit. I don't imagine this card will ever be played in any good priest deck.

I'm not too impressed. It gives less than ideal stats, and the lifesteal may not be enough to make it worth playing. Unless priests really need the extra healing, I don't think this will make the cut over other buff cards.

2 mana 2/4 is good enough to see play in any tempo based deck. The lifesteal just makes it less useless in the later game. I see no reason why it shouldn't see play in any dragon priest deck. And this, alongside Scalerider, may very well be enough of an early game advantage to make a dragon priest viable.

A nice tool for a zoo type priest deck, though I am not entirely sure how powerful this is.

On one hand, Shadow Ascendant was a powerful enough card, and now we have more support for that archetype. 

But on the other hand, it comes out 1 turn later, which matters a lot in the early game. I wouldn't expect this to survive more than a single turn. And if you only get one proc out of this, is it worth it?

I am not sure what to do with this card. There doesn't seem to be a combo deck where you could abuse this card to deal lethal damage, and if you really wanted to simply summon a copy of a minion then there is always Faceless Manipulator. I don't think this card will be too useful unless we get a minion valuable enough to combo this with. We have Reliquary Prime, but other than that I don't know exactly where you would want to use this card.

I don't like it. 7 mana it too much to only be playing a taunt minion. I don't expect you will get more than 1 random dragon off of this, and a single random dragon isn't worth the mana investment.

I mean, this is interesting, but is it really worth it? How many buffs spells are you playing in your deck so that by the time you have drawn this guy twice you still have enough buff spells to make the prime version an actual threat? This card is made to be in a board based buff type deck, and maybe it will be good in a deck like that, but I just don't see this guy as being as much of a threat as the other primes.

A+ Priest card. You either clear the board, or build a big enough board to be able to combat your opponent. This will be a staple in any priest deck that isn't either an Aggro deck or a Resurrect deck. 

This card is alright. It is not very exciting, but you will play it when you have to. 

I really like this card. It is small, simple, not too powerful, but good enough. If you want buffs, then this is good. If you want to cycle through your deck, then this is good. Or if you just happen to be playing a lot of minions in your deck then you could also play this and get away with it.

A very powerful card indeed. It only hits enemy minions, and it also gives you a tool able to kill them all. I could see you wanting to play this in a deck without the other Libram stuff.

This card isn't very good by itself, but if you are already playing the Libram package then I guess you might as well?