10. Ben 10,000 Returns

Complete story — includes the ending

In an alternate future, a different version of Ben 10,000 defeats Eon and seemingly destroys him using Clockwork's powers. However, Professor Paradox appears and reveals that Eon was merely sent back in time twenty years. In the present day, Ben, Gwen, and Kevin arrive at a museum to investigate a signal that the Ultimatrix received. They find a mysterious artifact and are attacked by ninja-like assailants who emerge from it; they defeat the ninjas, but before they can unmask them, the ninjas vanish. Gwen performs a spell on the artifact and sees into another reality (the world of Ben 10: Race Against Time ), where Ben, Gwen, and Grandpa Max are confronting Eon. Paradox and Ben 10,000 then appear, explaining that the artifact is the Hand of Armageddon, a gateway that leads to different parallel universes. After being defeated by the Ben from Race Against Time, Eon began travelling between worlds, killing every version of Ben Tennyson he could find. The group resolves to destroy the Hand of Armageddon before Eon can enter their world; however, as the two Bens begin to destroy the device, Paradox realises that Eon is instead using their powers to open a crosstime breach. Eon emerges and is revealed to be another alternate Ben Tennyson, who has been absorbing other Bens and making them his slaves. He intends to gain enough power to replace the timeline with one where only he exists. However, Ben is able to destroy the Hand of Armageddon, seemingly destroying Eon. Ben 10,000 then returns to his timeline, while Paradox ominously warns Ben about "Old George," and the "creature from beyond." Ultimatrix alien debuts: (By Ben 10,000) Ultimate Ben, Clockwork