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Iceman

Real Name: Robert 'Bobby' Drake

First Appearance: Uncanny X-Men #1

Group Affiliation: X-Men, formerly X-Factor, Defenders, Champions

Powers: Ice manipulation

Iceman was one of Charles Xavier's original X-Men. Eventually leaving the team, he founded the Champions, joined the Defenders (issues #122-152), and then founded X-Factor with the rest of the original X-Men. After the Muir Island Saga, Bobby returned to the X-Men and has since learned more about his ice-based mutant powers thanks to Emma Frost, who possessed him briefly after coming out of a coma. He has recently taken a leave of absence from the X-Men to spend more time with his father. He returned to rescue Cecilia Reyes from Prime Sentinels during Operation Zero Tolerance.

Impulse

First Appearance: Uncanny X-Men #107

Group Affiliation: Imperial Guard

Impulse is a member of the Imperial Guard, protectors of the throne of Shi'Ar.

Infectia

First Appearance: X-Factor #29

Last Appearance: X-Men #27

Cause of Death: Legacy Virus

Major Enemies: X-Factor

Infectia was a mutant with the power to transform people into monstrous beings with a kiss. She contracted, and eventually succumbed to, the Legacy Virus.

Iron Curtain

Real Name: Simas (full name unrevealed)

First Appearance: X-Factor Annual #1

Cause of Death: Killed by Firefox

Group Affiliation: Exiles

Major Enemies: Firefox, Doppleganger

Iron Curtain was a member of Blind Faith's Exiles, a team of Russian mutant freedom fighters encountered by the original X-Factor. He was killed by the Russian agent codenamed Firefox.