Ghost

The original Ghost was a corporate saboteur and computer engineer who fused himself with his own phasing technology, erased his identity from every record on Earth, and declared war on multinational capitalism. He was one of Iron Man's most conceptually unsettling opponents: an enemy who cannot be found, cannot be touched and does not want money.

The MCU reimagined the character as Ava Starr, daughter of a S.H.I.E.L.D. scientist killed in a quantum accident that left her permanently unstable at the molecular level. Her phasing is constant, painful and slowly killing her, which turns a straightforward antagonist into someone doing terrible things for an understandable reason. Both versions ended up on the Thunderbolts, which is the correct home for anyone whose defining feature is being impossible to hold.

David Michelinie and Bob Layton created Ghost in Iron Man #219 as an anti-corporate terrorist with no name and no traceable history, and the character became one of the more durable Iron Man antagonists of the era.

Warren Ellis and Jeff Parker both used Ghost extensively in Thunderbolts, where his refusal to explain himself and his complete disinterest in the team dynamic made him quietly one of the book's best characters. The 2018 film swapped in Ava Starr, and Thunderbolts* carried that version forward.