Greystone was part of the XSE (Xavier Security Enforces) along with Bishop, Shard, Fixx and others. When Bishop came to our time, the XSE followed to arrest Trevor Fitzroy.
As time passed, Greystone and Fixx had involved themselves with X-Factor. Greystone would later accuse Multiple Man of treason. Soon afterwards, Greystone lost his control and wanted to run away. Greystone caught the X-Factor's ship, Havok tried to hinder, but the ship exploded. Greystone apparently perished in the explosion.