Sure, each Super Hero is strong on their own. But when they team up, they can become unstoppable. Through their various training regimens, Heroes of a team can create special strategies that play to the teams strengths. The Team Decks expansion for Marvel United gives players the option to add a special set of cards to their games. By restricting the available heroes and using the highest Challenge Level, players gain access to a Team Deck of cards, using one of them instead of their own Hero Card on their turns. Just watch out for ones with manda tory negative effects.