David kept his powers hidden from those around him as he excelled academically. A chance encounter with an anti-mutant group and Dani Moonstar lead him to enroll in the Xavier institute. There he was placed on the New Mutant training squad and was asked to b leader though he declined. Under the leadership of Sofia Montega the team lost a training match to the Hellions and when teammate Wither was arrested he eventually became co-leader of the team.
When his sister Kim visits they have a brief encounter with a ghost before Emma Frost ad him experience his worst fear in which he became a tyrant and caused the deaths of his friends. When the world’s mutant population was de-powered David was one of them though he remained at the school when William Stryker killed the de-powered student body on a bus. He also started a romantic relationship with Noriko Ashida. Danger stroke however as he was dragged to hell when Magic was brought back to life, him and Noriko then broke up after she kissed Hellion. The stepford Coo-coos then used there powers to help him remember everything he had absorbed or learned when he had his powers.
He helped rebuild Cerebro when the mutant messiah was born after relocating to San Francisco with Cyclops. Since then he has been an integral part of the support team on Utopia. After Idie Okonkwo kills some humans to save the x-men he consoles her.
Before he lost his powers on M-day he possessed Psychomimicry which endowed him with the mental skills and knowledge of those within his vicinity. It usually wore off once the person moved out of his vicinity though their knowledge remained in his muscle memory. This power also as a side effect allowed him to read the body language of those around him allowing him to avoid attacks directed against him. He is currently unable to acquire new skills as he lost his powers on m-day and is now human.