Lord X is a demon who exists outside the barriers of reality. He manifested himself in a PC ported copy of Sonic The Hedgehog, and lures victims in to play his demented games. As of now, his “harbingers” now consist of Tails Prower, Dr Ivo Robotnik (whom he just calls him “Doctor”), Knuckles The Echidna, and Amy Rose. 

Lord X disposed of Sonic by forcing him into a dark and twisted void, where he suffers for eternity without his beloved world or Sally Acorn. 