XL is a (former) antagonist of Buzz Lightyear of Star Command. He a is robot who is the predecessor (and technically older brother) or XR (one of the supporting protagonists of the series).
XL was shut down due to his villainous attitude. When he was reactivated by Emperor Zurg, XL rebuilt himself into a larger, more powerful robot with cutting edge (and stolen) robot parts. He infiltrated Star Command numerous times because its command codes are in his head. Like XR, he considers Commander Nebula his father, though he resents him for shutting him down.
However, in the episode Revenge Of The Monsters, he helped Buzz Lightyear and XR to stop Nos-4-A2 from infecting everyone else into Wirewolves. Following Nos-4-A2's death, XL was back in Star Command as a copying machine and he joined the Star Command staff.
- His name is a pun referring to his size (extra large).