XR

XR (Experimental Ranger, though some believe his name actually stands for Expendable Ranger) is a short, irresponsible robot who currently works as a Space Ranger on Star Command.

XR was created by the Little Green Men. Commander Nebula unknowingly authorized his creation when the LGMs slipped the request together with their vacation request forms, since they knew the Commander would sign it without reading, as he hates doing paperwork. As a result, XR considers Nebula to be a father figure, much to the Commander's annoyance.

At first, XR was given to Buzz Lightyear as a new partner. At that time the robot still had no personality and was merely programmed to learn things from Buzz, and doing this by repeating every single sentence he said. During their first mission, an unsuccessful attempt to prevent Evil Emperor Zurg from stealing the LGMs' Unimind, XR was destroyed. Without the Unimind to provide their mindlink, the aliens lacked the knowledge to rebuild XR properly and as a result he became more Human and developed a personality of his own, with several character flaws.

After this, XR was given to Booster the janitor as an assistant. The two ended up going on an important mission with Buzz and helped him to defeat Zurg and save the galaxy, after which Buzz decided to accept Booster and XR on his newly created Team Lightyear.

In spite of his cowardness and lack of responsibility, XR is quite a useful robot. He has extendable arms and legs, many pop-out gadgets and a chest cavity where he can store several objects. He is also easily rebuilt if destroyed. XR's head is not attached to his body, floating freely inside his space helmet. He also has two extra, retractable arms, like Stitch does.