Appearing in Sonic the Hedgehog #264, Xi attacked three of the Freedom Fighters - Sonic the Hedgehog, Princess Sally, and Amy Rose - when they entered the territory of Egg-Boss Thunderbolt, to whom Xi had been lent. It pursued Sonic doggedly, only to run into his allies Mighty the Armadillo and Ray the Flying Squirrel. Ray flew Sonic out of Xi's reach, while Mighty swiftly dispatched the robot, much to the chagrin of the Soumerca Egg Army.
Appearance and abilities
Xi possesses a similar design to the other E-100 models, with a rounded body and flat head. Its head casing is yellow, it has green optics and an orange and white body. Its design is loosely based on a simian or cat; its form is meant to run on all fours and it has sharp claws on each of its appendages, allowing it to slash foes or grip surfaces. Its long, cable-like tail ends with a laser blaster.