Doctor Thomas Light is the former colleague of Dr. Albert Wily, and creator of MegaMan, as well as many other robots, including ProtoMan and X. He was confirmed deceased just before X's sleep, and just after the disappearance of Rock (MegaMan) and Roll (Rock's "sister"), but he lives on inside his computer database. Somehow. Look, I can't explain it either, so it's better to just not ask, ok? Ok.