It has happened before, it is happening now, it will surely happen again. A group, perhaps a team or organization or even an entire race like humanity, suddenly gain the same abilities? The same talents? The same powers? Everyone gets power rings, everyone gains the power of the Hulk, everyone becomes Vampire Slayers... These are the stories of those occasions where people develop the same, or maybe just similar, powers to the extra-ordinary person we read or watch about. Some force has given their powers and abilities to more then one person. How does the world react? Is this permanent, temporary, reversible, or something else?
Another variant of the tale is where a team or group, heroes or villains or both, gain the same/similar powers as each other member of the team. For instant, each member of the Avengers/Justice League/etc gains the equal power of all other members of the team. Does this affect only current members or all members past an present? If the later, what about heroes who have joined villain teams or vice versa? Those stories are also revealed here, starting with...