With the ability to mimic the powers of mutants, Calvin Rankin served as both an ally and an enemy to the original X-Men.
Although he never joined the Defenders in the mainstream Marvel Universe, the version of Mimic who joined the dimension-hopping Exiles told how he had been a member of the Defenders in the a parallel universe he called home (Exiles #3).
- Mimic: Yes, not my finest hour. You should have seen my costume…
It's unclear if the costume Mimic wore with the Defenders was the same costume worn during his original X-Men appearances.
When the Exiles journeyed to an alternate timeline where the X-Men prepared to fight the Imperial Guard to save Jean Grey/Dark Phoenix (mirroring X-Men #137), that world's version of Wolverine was surprised to see Mimic.
- Wolverine: So what's up, bub? Ain't you supposed to be running around with Doc Strange and Iceman?
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We can only imagine what other ways the Defenders of this world might have been different.