Curvill is a power-type Zoanoid that appears to resemble a humanoid wolf. It is theorized that this creature is one of the original Zoanoid types originally produced by the alien Creators and that over the centuries since the Creators left Earth, Zoanoids of this particular gene configuration have re-emerged on several occasions and given rise to the legends and folk tales regarding werewolves.

In many respects, Curvill is much like the legendary werewolf. It possesses uncanny senses of smell and hearing and can move easily on all fours or upright.