X1

X1 is the Director's oldest test subject, and is held in the Cerberus space facility known as the Barn. The subject is a krogan that has undergone significant genetic and cybernetic augmentation. It is several times larger than a normal krogan, with significant alterations made to forelimb size and overall muscle mass. It has also been enhanced with cybernetics in the form of energy weapon gauntlets and integrated shield generators.

X1 appears incapable of speech. It is unknown whether it is controlled by Cerberus through indoctrination or if it has simply gone insane after the experimentation its been put through.