I really like those, especially the hunter and the warrior ones, but I can't ignore the fact that the Theramore Guard is using a Scryer Tabard...
I think the mana tree would be better as 1 mana 0/1. But that's just me.
My only objection is about the Theramore Guard. It's a Warrior card (Image Garrosh using Theramore Guard vs Jaina, lol), and it's a blood elf in the image, where it should be an Alliance race (A high elf at the least).
Guard nice addition to bolster warrior, or control.Experiment well, awsome idea but not AI is not smart enough.Buddy seems nice.Tree should cost 4 for this text and stats, 3 maybe to powerfull.Altairus you just no need it shaman is random enough already, play bloodlust.
Altairus could be a tad more viable if it read, Battlecry: Give adjacent minions Windfury or Can't Attack at random.But only by a tad.
That Arcane Experiment would be a fun card. It's a risk to give your hand over to the AI but the AI's play can be predicted so you have a bit of control in that you can choose what hand to use it with.Loyal Buddy is cute :)
Everyone faced Thaurissan once shall remove Loyal Buddy ASAP.Mana Tree may be useless if drawn late - unless it gives you Excess Mana in that case.Altairus just looks like Mogor the Ogre with one-time RNG. Hope you have Earth Shock.
Theramore Guard seems like it wouldn't make Bolster Warrior a thing, but I can see it in Fatigue Warrior. Arcane Experiment seems very "experimental" (sorry), but it seems like it could lead to broken combo decks where you empty your hand and let the computer see lethal or drop some giants. Loyal Buddy seems like an auto two-of in Beast Hunter, but I think it would be an optional card in Middy Hunter. Unplayable in Face Hunter. Mana Tree seems bad. It would really need a buff to see any sort of play. Maybe more like a Nat Pagle effect: 50% chance for a crystal at the end of your turn with 2 mana 0/4 stats. Finally, Altairus is extremely interesting but probably wouldn't see any play.
Pretty @#$%ty cards.