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- Iceman in X-Men #1
- Ikaris in Eternals #1
- Impossible Man in "Fantastic Four" #11
- Impossible Woman in Marvel Two-in-One #60
- Impulse in New Warriors #4
- In-Betweener in Warlock #10
- Inhumans in Fantastic Four #45
- Interloper in Defenders #147
- Invisible Woman in Fantastic Four #1
- Iron Fist in Marvel Premiere #15
- Iron Man in Tales of Suspense #39
- Isis in Thor #240
- It the Living Colossus in Tales of Suspense #14
Read more about this topic: List Of First Appearances In Marvel Comics Publications