Here are some other great ideas on the I&FR sub-forum. To view the thread, click on the respective card picture.
Created by: Cutioner
Unlockable in: Hog Mountain
Card Description: Some wizards just love to see the world contaminate! Drops a nasty Poison Spell when killed, but still leaves the grass green!
*Note that the card picture is not official.
Created by: Sammydict
Unlockable in: Unknown
Card Description: He throws magical cards to deal damages and becomes a handsome statue under attack.