Xarians
From superman.nu: Supermanica
Xarians
Peaceful aliens who come to Earth to warn of a destructive computer brain that they have made and is now running amok. With Superman and Supergirl off on a space mission, Jimmy Olsen steps in to lead the Xarians into battle to stop the brain from constructing diabolical machines. Despite his military leadership ambitions, Olsen is lucky that Superman and his cousin return in time to stop the threat (SPJO No. 60/3, Apr 1962: "The Fantastic Army of General Olsen!").
