Hemisphere Raiders

Formed after brain removal equipment was leaked to a raider group

Leader of the group wanted to create a copy of himself

Had half of his brain removed and implanted into a mare’s body

This caused a divide between the two brain halves as they developed different ideas of how to lead. This split the raiders into two groups each following one of the brain halves

To show loyalty, some high-ranking members voluntarily have half of their brain removed, whichever half their leader is missing. This results in a half-derped expression and persistent drooling.

Groups and leaders are called 'Lefty' and 'Righty' respectively.