Doomskull is the last Beast Tom must fight in the Master of the Beasts series. This Beast was actually defeated by the Gold Knight long ago.
Doomskull is a giant stone lion with huge paws and a long tail. He has long fangs and sharp teeth. He has two empty eye sockets and on top of his head he has flames.
The Gold Knight defeated this Beast long ago. Malvel wanted to capture Avantia and bewitched the Gold Knight to become his former foe.