Cyclops, the leader of the mutant race decided so to use all of his resources on hand, and asked Charles Xavier to use the Legion as a weapon against the Sentinels.
Xavier then launched the Nemesis Protocol, calling the personas to fight for Legion. 115 was the first personality selected during the battle, arriving just at time to save the overwhelmed and wounded Colossus. Her powers were soon assimilated by the Nimrods' defenses, and she had to leave her place to 762.
Powers and Abilities
Acoustikinesis: 115 was able to create powerful sonic beams from her hands, powerful enough to blow up a Nimrod. This power was deemed "Acoustic-Aggressive" by the Nimrod Sentinels.
The Nimrods' adaptation was to emitting white noise, making 115's powers useless.