X-O Manowar

Gender: ♂
Universe/Dimension/Timeline: Valiant Universe

Features
Iron Man/X-O Manowar: Heavy Metal (Valiant / Marvel) 1.FT
X-O Manowar/Iron Man: Heavy Metal (Valiant / Marvel) 1.FT

Xorn

Gender: ♂
Alternate version(s): Xorn (AgeOfApo)
Individual of: Mutants
Member of: X-Men I

Features
The Official Handbook of the Marvel Universe: X-Men 2005 1.FT
X-Men (II) • New X-Men (I) • X-Men Legacy (I) 200.FT

Xorn (AgeOfApo)

Gender: ♂
Alternate version of: Xorn
Universe/Dimension/Timeline: Earth Age of Apocalypse (Earth-295)

Xorr the God-Jewel

Xorr
Gender: ♂

Features
Marvel Legacy: The 1960s-1990s Handbook TPB 1.FT
Marvel Legacy: The 1970s Handbook 1.FT
Secret Invasion TPB: Who Do You Trust? 1.FT
Skrulls! • Secret Invasion Skrulls! 1.FT

X-Patrol

Alternate version of: X-Men I
Universe/Dimension/Timeline: Earth Amalgam

Xraven

Gender: ♂
Clone/Copy/Impersonator of: Kraven the Hunter
Created by: Mister Sinister
Powers taken from: Angel I, Beast I, Cyclops I, Iceman I, Marvel Girl I

Features
Heroic Age: Villains 1.FT
X-Men Earth's Mutant Heroes 1.FT

X-Ray

James Darnell
Gender: ♂
Member of: U-Foes
Sibling(s): Vapor

Features
Essential Official Handbook of the Marvel Universe Deluxe Edition 2.FT
Essential The Official Handbook of the Marvel Universe Master Edition 3.FT
New Avengers Director's Cut 1.FT
New Avengers Marvel's Greatest Comics 1.FT
The Official Handbook of the Marvel Universe Deluxe Edition 13.FT
The Official Handbook of the Marvel Universe Master Edition 10.FT

X-Sentinels

Member(s): Angel Robot, Cyclops Robot

X-Statix

Alias of: X-Force III
Member(s): Dead Girl, Doop, Guapo, Mister Sensitive, Phat, Spike, U-Go Girl, Venus Dee Milo, Vivisector

Main
X-Men Unlimited (I) 41
X-Statix Omnibus (HC) 1
X-Statix TPB 2

Features
Anita Blake: Circus of the Damned - The Scoundrel 1.FT
Avengers (V) 17.FT
Avengers: The Children's Crusade 7.FT
Captain America (VII) 3.FT
Generation Hope 11.FT
Heroes 1.FT
Ka-Zar (IV) 4.FT
The Official Handbook of the Marvel Universe: Teams 2005 1.FT
Ultimate Hawkeye • Ultimate Comics Hawkeye 2.FT
X-Factor (IV) 225.FT
X-Men (III) 18.FT

X-Terminated

Member(s): Deadeye, Fiend, Goodnight, Horror Show, Prophet
Universe/Dimension/Timeline: Earth Age of Apocalypse (Earth-295)

X-Terminators I

Subgroup of: X-Factor I

Features
Essential Official Handbook of the Marvel Universe Deluxe Edition 3.FT
The Official Handbook of the Marvel Universe Deluxe Edition 15.FT

X-Terminators II

Member(s): Boomer, Russell Collins, Leech, Arthur Maddicks, Rictor, Skids, Wiz Kid
Subgroup of: Mutants

Main
The New Mutants Annual 7

Features
Essential Official Handbook of the Marvel Universe Update '89 1.FT
The Official Handbook of the Marvel Universe Update '89 8.FT

X-Ternals (AgeOfApo)

Member(s): Lila Cheney (AgeOfApo), Gambit I (AgeOfApo), Jubilee (AgeOfApo), Strong Guy (AgeOfApo), Sunspot (AgeOfApo)
Universe/Dimension/Timeline: Earth Age of Apocalypse (Earth-295)

Features
X-Men: Age of Apocalypse One Shot 1.FT
X-Men Chronicles 1.FT

X-Treme

(Adam X)
Created by: Fabian Nicieza, Greg Capullo, Jeff Johnson
Gender: ♂
Parent(s): D'Ken Neramani

Features
Marvel Legacy: The 1960s-1990s Handbook TPB 1.FT
Marvel Legacy: The 1990s Handbook 1.FT
X-Men: The Ultra Collection 4.FT

X-Treme Sanctions Executive (X.S.E.)

Features
X-Men: Future History - The Messiah War Sourcebook 1.FT

X-Treme X-Men I

Subgroup of: X-Men I

Features
Marvel Poster Magazine 1.FT
X-Men: Future History - The Messiah War Sourcebook 1.FT

X-Treme X-Men II

Member(s): Dazzler I, James Howlett (XtX), Emmeline Summers-Frost, Kurt Waggoner, Charles Xavier (XtX)