Deadman

Boston Brand a.k.a. Deadman is an undead superhero in the DC comic universe. Deadman has the powers to possess others, fly, pass through matter and even travel between the worlds of the living and dead. While in a body in addition to any physical strength or powers his host might have Deadman is capable of using great fighting skill and nimble reflexes regardless of the any lack speed or fighting prowess said body normally be restricted by.

Boston Brand was a trapeze performer in a circus who was murdered by an assassin. His violent and seemingly unprovoked death caused Boston to come back as a ghost, leaving confused about his death and his state of existence as an undead being in general. Boston found several new rules applied to him as a ghost; Boston found he could not move objects in the physical world however he also could not be stopped by things like walls, earth or gravity, he found he could not change his clothing, leaving him stuck wearing his acrobats' tights and white rubber mask he used for the performances and he found that short of certain psychics and mystics he could not be heard seen or sensed in anyway by normal people, however such an issue could be circumvented through his new ability to possess people.Once Boston had grown accustom to his new state he focused on solving his own murder and took up the mantle "Deadman" in his search.

Deadman eventually found the person who killed him, a man called Hook, who was part of Ra' al Ghul's League of Assassins, as it turned out Boston's death was not personal but rather just a rite of passage for Hook to prove himself to the League. Deadman spared Hook's life and was more or less content just with the knowledge of what had happened to him and went to rest in peace...and then found he still couldn't. Boston was contacted by Rama Kushna, a demi-goddess who represented karma. Deadman was in a rather unique position as a ghost who had resolved his unfinished business without being ruled by sorrow or vengeance and as such had the opportunity to make right various other karmic imbalances, a position the forces that be were quite insistent he exploit for the sake of cosmic balance. And so with Rama Kushna as his contact Deadman went throughout the world of the living preventing catastrophe's, resolving events that were never supposed to have happened in the first place or helping beings of great spiritual significance with the promised his reward being a proper death when he was done.

Deadman went through many overseers rotating out from Rama Kushna to various mystics giving him guidance, He has been a close companion of Constantine and even a member of the Black Lantern Corps eventually. Eventually Deadman was given his reward, however far form being eternal rest as he thought it turned out he was granted the ability to come back to life. Deadman is part of DC's universal rebirth of their issues called The New 52, in it Hook is redone as an over the hill mobster who murdered Boston to reprove his skill as criminal but is spared by Deadman when he finds him because of not wanting to put his family through the lose.