The cat is out of the bag. In 2015, The Avengers will face Ultron in Avengers: Age of Ultron. The malevolent mandroid was first seen in the pages of 1968's Avengers #54. The repugnant robot was initially built by Ant-Man, but became sentient and tried to enslave the world. Ultron is a worthy foe for the Avengers and has squared off against the team onscreen a few times in the past.