- Pencils
- ?
- Inks
- ?
- Letters
- typeset
- First Line of Dialogue or Text
- Fun Factory
Inside front cover. Ad for various novelty items.
- Script
- John Byrne (credited) (plot); Chris Claremont (credited) (plot, script)
- Pencils
- John Byrne (credited)
- Inks
- Terry Austin (credited)
- Colors
- Glynis Oliver (credited as Glynis Wein)
- Letters
- Tom Orzechowski (credited)
- Job Number
- LG580
- First Line of Dialogue or Text
- Ever hear a city scream?
- Genre
- superhero
- Characters
- X-Men: Banshee [Sean Cassidy] (featured); Colossus [Piotr Rasputin] (flashback) (featured); Cyclops [Scott Summers]; Nightcrawler [Kurt Wagner] (featured); Phoenix [Jean Grey] (flashback) (featured); Storm [Ororo Munroe] (featured); Wolverine [Logan] (flashback) (featured)
Jennie Banks (flashback) (possessed by Proteus); Ferdie Duncan (flashback) (possessed by Proteus); Fred Duncan; Havok [Alex Summers]; Moira MacTaggert (flashback) (supporting); Angus MacWhirter (flashback, death) (cameo) (possessed by Proteus); Magneto [Max Eisenhardt] (flashback) (cameo); Multiple Man [Jamie Madrox] (flashback) (cameo); Polaris [Lorna Dane]; Proteus [Kevin MacTaggert] (death) (villain) (as Joe MacTaggert, apparent death); Mike (first appearance)
- Universe
- Marvel : mainstream
- Synopsis
- It's the X-Men vs. Proteus to the death.
- Reprints
- in Marvel Masterworks: The Uncanny X-Men (Marvel, 2009 series) #4
- in Spécial Strange (Editions Lug, 1975 series) #28 (10 juin 1982)
- in Superaventuras Marvel (Editora Abril, 1982 series) #23 (Maio de 1984)
- in Prosjekt X (Semic, 1984 series) #4/1985 (uke 15 1985)
- in Die Gruppe X (Condor, 1985 series) #7 (1986)
- in Classic X-Men (Marvel, 1986 series) #34 (June 1989)
which is reprinted- in El Asombroso Hombre Araña Presenta (Novedades, 1988 series) #103 (Abril 5 de 1990)
- in Essential X-Men (Marvel, 1996 series) #2 ([August] 1997) [black and white]
- in Marvel Special (Marvel Italia, 1994 series) #11 (Agosto 1997)
- in Wizard X-Men Masterpiece Edition (Marvel; Wizard, 2003 series) #1 (December 2003)
- in Marvel Masterworks: The Uncanny X-Men (Marvel, 2003 series) #4 ([October] 2004)
- in The Uncanny X-Men Omnibus (Marvel, 2006 series) #1 (2006)
- in X-Men: Proteus (Marvel, 2009 series) (2009)
- in Marvel Gold. La Imposible Patrulla-X (Panini España, 2011 series) #2 - Días del Futuro Pasado
- in X-Men Classic (Panini France, 2012 series) #4 (décembre 2012)
- in X-Men Epic Collection (Marvel, 2014 series) #6 - Proteus (2020)
- in Phoenix Omnibus (Marvel, 2021 series) #1 (2021)
- in X-Men - La Collection Mutante (Hachette, 2020 series) #39 - Foudre cosmique (mars 2022)
From X-Men # 125, the titles of each episode are inspired by a quote from Shakespeare. That is the last: "Then imitate the action of the tiger" (Henry V. Act III, Scene I). Its meaning is linked to the sentence it precedes, "Stiffen the sinews, summon up the blood ..." which refers to the final fight against Proteus.
- Script
- Stan Lee; ?
- Pencils
- ?
- Inks
- ?
- Colors
- ?
- Letters
- typeset
- First Line of Dialogue or Text
- Hoo boy! Looks like I did it again!
- Characters
- Biotron; Bug; Marionette; Arcturus Rann
Includes an image of Marvel Comics #1.
- Pencils
- ?
- Inks
- ?
- Colors
- ?
- Letters
- typeset
- First Line of Dialogue or Text
- Hey kids! Win a fantastic trip to a faraway place and be on Journey to Adventure
Ad for Popsicles and an entry into a sweepstakes.
- Pencils
- ?
- Inks
- ?
- Colors
- ?
- Letters
- ?
- First Line of Dialogue or Text
- New! Electronic action toy!
- Characters
- Rom
Inside back cover. Ad for an action figure of Rom the Spaceknight.
- Pencils
- ? (photos)
- Inks
- ? (photos)
- Colors
- ? (photos)
- Letters
- typeset
- First Line of Dialogue or Text
- You've got to build 'em to believe 'em!
Back cover. Ad for the Lego expert builder series.