Hot Wheels Battle Force 5 S01E22 - Gladiators

The BF5 enter the Gladiator Zone to retrieve a battlekey. As they fight the Vandals, both sides end up becoming prey to a larger foe. It turns out the zone is controlled by a mysterious robot named TORS-10, who pits the Vandals and BF5 against each other in gladiator-like bouts.