The Marvel: Crisis Protocol Sin and Viper Character Pack introduces two notable villains from the Marvel Universe. Sin, the heir to Red Skull’s legacy, possesses enhanced abilities and frequently collaborates with Crossbones, posing a threat to heroes such as the Avengers and the Winter Soldier. Viper, originally trained by Hydra, now commands the Serpent Squad as a skilled and ruthless operative in the criminal underworld. Both characters are well-known among Marvel Comics fans and offer strategic versatility in gameplay, particularly within the Cabal Affiliation, due to their distinct abilities. The pack includes detailed miniatures for tabletop play.