The majority of its publications takes place with the fictional Marvel Universe and its most well-known teams include the Avengers, the Fantastic Four, the Guardians of the Galaxy, the Brotherhood of Evil Mutants, the Dark Avengers, the Eternals, the Defenders, the Inhumans, the Thunderbolts, the Runaways, the Sinister Six, the S.H.I.E.L.D., and the X-Men.