Mastermind is one of the non-playable characters in LEGO Dimensions 2: The Rise of Enoch, from the Marvel Comics franchise.
Jason Wyngarde, a.k.a. Mastermind, is a Mutant with the power to create realistic illusions. He was one of the original members of Magneto's Brotherhood of Evil Mutants, and later became a member of the Hellfire Club. He used his illusions to get Phoenix into the Hellfire Club, which caused her corruption into Dark Phoenix.