Doctor Demonicus (Douglas Birely) is a fictional character, a supervillain appearing in American comic books published by Marvel Comics. He possesses advanced knowledge of genetic engineering and has clashed with the Avengers and the Shogun Warriors, in addition to S.H.I.E.L.D.
Vote which fictional character would naturally fit in-universe with a big-named franchise! No time-travel, no interdimensional crap, no "Pooh's Adventures", they would just exist in-universe.
