"I want to be in the form of WATER!"
These characters were only created for this show. Zan, Jayna, and their pet space monkey Gleek came to Earth from the planet Exxor. They are in training to become full fledged superheroes. When they touch hands, the Wonder Twins activate their powers... Jayna can change into any animal, while Zan can change into any form of water & ice. (Yeah, I think that's a dumb power too.)
ROFL. That looks SOOOOOO cheesy, but I know you generally have good taste, so I'll assume it's really not! ;o)