Banshee, forced to submit to the Mutant Master's commands via a headpiece rigged to explode should he refuse, teamed up with The Ogre to kidnap Professor Charles Xavier.
[5] Later, Factor Three freed the supervillain Juggernaut, serving to distract the X-Men while a second attempt was made to kidnap Professor X; this time they succeeded.
Factor Three relocated to an alternate base, where Changeling, Mutant Master's second in command, discovered his plans to destroy mutantkind as well as humankind.
Changeling freed Professor X and Banshee, who inadvertently destroyed the Mutant Master's cloaking device, revealing his alien appearance.
The X-Men and the remainder of Factor Three joined forces in attacking Mutant Master, who committed suicide to avoid capture.