The ThunderCats are on the move! After the kingdom of Thundera is attacked by the lizard people, Lion-O leads Tygra, Cheetara and the other heroes on a quest for the Book of Omens and the magic stones of legend. But he'll have to face villains like Mumm-Ra, the ancient evil sorceror, and Slithe, the dangerous lizard general. Luckily, he has the Sword of Omens and its amazing powers at his disposal.