Gambit and Nightcrawler are fan favorite mutants in the X-Men series, and Mr. Singer had stated the following:
"I’m considering a Gambit and potentially a young Nightcrawler for Apocalypse," Singer said. "[I was] going to have Nightcrawler appear [in Days of Future Past], and even wrote a scene, but I felt that we were forcing too many mutants known history."
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