Xylene is an alien friend of Grandpa Max's, and she was also the person transporting the Omnitrix when Vilgax attacked. She sent the Omnitrix to Grandpa Max, but it veered off-course to Ben. After we find this out, a giant robot attacks, but Ben defeats it. It attacks again and steals Grandpa Max, so Xylene, Ben and Gwen go to stop it. The robot merges with a tank and is impossible to beat until Xylene touches the Omnitrix and Ben transforms into Upchuck, a strange green alien with four tongues and a big appetite. He eats the robot and finds that he can spit explosive balls. Xylene then asks Grandpa Max to come to space with her, but he turns her down.