A.I.M. is a fictional criminal organization appearing in American comic books published by Marvel Comics. Created by Stan Lee and Jack Kirby, it first appeared in Strange Tales #146. A.I.M. is primarily depicted as a think tank of brilliant scientists dedicated to world domination through technological means.

Hydra is a fictional terrorist organization appearing in American comic books published by Marvel Comics. Its name alludes to the mythical Lernaean Hydra, as does its motto: "If a head is cut off, two more shall take its place," proclaiming the group's resilience and growing strength in the face of resistance. Originally a Nazi organization led by the Red Skull during World War II, Hydra is taken over and turned into a neo-fascist international crime syndicate by Baron Wolfgang von Strucker. Hydra agents often wear distinctive green garb featuring a serpent motif. Hydra's plans for world domination are regularly foiled by Marvel Universe superheroes and the intelligence organization S.H.I.E.L.D.