I think "Planeswalker" might have gotten around the censors... Oh wait magic.
First the cards are awesome, and really the biggest issue with them is costs or numbers. This game has plenty of overpowered effects already, Theres no reason any of these cards could completely throw off the game balance because of cards like lobatomizer and sundials. Let me go through what I think about each one specifically.
Bazuul: I love the effect. Its like a fire shield but also targets creatures that do not attack. I'd drop its attack to 9, and incread health to 20 though. That kind of offense on a card with an effect that kills other creatures for no mana is a bit ridiculous.
Chosen One: The pick is pretty damn funny. Some people actually believe that. As for the card, reduce the defense to 15 or so, and let the hero gain from the +1/+1. I doubt many decks could neutralize that creature fast enough when its gaining from its own effect.
Clockmaker: The card concept is good, but time is really powerful in controlling the enemy as is. I could see this card becoming way too powerful. Either the bubble should last two turns or the cost for the ability should be doubled. You have to remember that time has lockdown effects that could potentially prevent the opponent from ever countering this card. Its almost balanced alone, but the combinations are too crazy.
Demon from the Depts: I'd make the ability more powerful. Maybe something like, "Three target creatures are frozen for four turns" I just really don't like randomization in stragety games.
The Joker: Looks fun. Probably a lower attack and higher defense though.
Rocky: Add a line: All enemy burrowed creatures take 2 damage. This is another canidate for lower attack higher defense.
Tree of life: Excellent card
Vampire lord: Fun concept, i really don't know about balance, darkness procuces alot of mana, but the effect is not quite as over-powered as some of the other heros.
Zombie King: Wow thats nasty.
Time Machine: Make sure theres no way to remove the gravity pull and the card will be fine.
Wyrm Queen: Seems kinda... boring, not sure what to say. In magic the usual thing to do would be give all air cratures flying with a card like that. maybe momentum in addition to the current effect.?
Immortal king: I'd like to see a more interesting effect, but really don't have any ideas.
Over all I love the cards!
EDIT: One more thing. Perhaps they should be unable to gain certian effects, especially immortality (if they don't have it already). Bascially they could be targeted, but only by direct damage or direct buffing stuff, or their own effects.
Like I said earlier, very good feedback. I can see you have played CCG's before
I totally agree with lowering attack for most of these cards. They are powerful even without high attack (although I would like to see 1 of them with relatively high attack and a bit weaker ability).
I'm not sure about improving their HP. In my experience if a creature has 20+ HP it's almost impossible to kill. Unless you have Eagle's Eye, Gravity Pull or a bunch of direct attack spells you probably won't be able to kill it. But it's difficult to say what would be a good balance. These kinds of things need testing.
What you said about
the Clockmaker is a great idea and I don't understand why I didn't even consider it. If time bubble lasted for 2 turns, it would be much better. That would mean that if you use it every time, you would get 3 turns when your opponent only gets 2, which sounds pretty good to me.
I think if
Demon from the Depths could freeze 3 characters every turn if would be WAY too powerful. Think about it. If the opponent had 9 characters on the table, that would mean in 3 turns they would all be frozen, and as soon as they unfreeze, they would be frozen again. I hate random thing too but that's how Ice Bolts and that Water Shield work in this game so I don't see that as a big deal.
Yeah,
Wyrm Queen IS kinda boring. I had real trouble trying to come up with something fun for Air. Most elements clearly have something "they are about", but I just didn't see that with Air. Something that flies is an obvious choice but since flying doesn't mean anything in this game.. what can you do? I don't know about adding momentum because it's Gravitys bread and butter.
Thanks a lot for posting your ideas. It was really helpful.