Wulf 1
Wulf is a ghostly werewolf with retractable claws that have the ability to tear holes between Earth and the Ghost Zone. He only speaks Esperanto, which only Tucker understands, but which later Sam and Danny learn.

Appearances in Danny Phantom

Wulf's first appearance was in "Public Enemies". Wulf was a prisoner of Walker, who sends him to find Team Phantom, in exchange for his freedom. But after meeting Danny, the two quickly became good friends. Danny, Sam, and Tucker did their best for Wulf, eventually freeing him from the shock collar Walker used on him through Tucker's PDA. In return, he helped Danny stop Walker.