Labeled "Earth's Mightiest Heroes", the Avengers originally consisted of Ant-Man, Wasp, Thor, Iron Man, and The Hulk (Captain America did not join until issue #4, although he was given the status of an honorary founding member). The rotating roster has become a hallmark of the team, although one theme remains consistent: the Avengers fight the foes no single superhero can withstand — hence their battle cry, "Avengers Assemble!" The team has featured humans, mutants, robots, gods, aliens, supernatural beings, and even former villains.