At ten, Ben Tennyson was ambushed by aliens after finding the Omnitrix, but Tetrax rescued him and Rook Blonko. Both orphans, they trained as space vigilantes. Ben later got the Ultimatrix, and at 20s, he and Rook returned to Earth, where it is unexpectedly protected by the Justice League. (Note: Each episode features different art styles due to multiple illustrators, do not what to overburden one illustrator, and to release each episodes faster. Thanks for understanding!)