- Script
- Chris Claremont (credited)
- Pencils
- Rick Leonardi (credited)
- Inks
- Dan Green (credited)
- Colors
- Glynis Oliver (credited)
- Letters
- Tom Orzechowski (credited)
- First Line of Dialogue or Text
- A mile beneath Manhattan... ... are the tunnels where the Morlocks lived...
- Genre
- superhero
- Characters
- Morlocks: Callisto (guest); Healer (guest)
X-Men: Colossus [Piotr Rasputin]; Magneto [Erik Lehnsherr]; Nightcrawler [Kurt Wagner]; Rogue; Shadowcat [Kitty Pryde]; Storm [Ororo Munroe]; Wolverine [Logan]
Tom Corsi (guest); Sharon Friedlander (guest); Moira MacTaggert (guest); Psylocke [Betsy Braddock] (guest); Sabretooth [Victor Creed] (villain); Morlocks (guests); Mr. Sinister (villain, first mention of)
- Universe
- Marvel : mainstream
- Synopsis
- Wolverine makes his way through Sabretooth to bring the Healer back to the mansion to tend the wounded. Nightcrawler, Kitty and Colossus are critically injured and taken out of action. The Morlock tunnels are purged.
- Reprints
- in La Patrulla-X (Planeta DeAgostini, 1985 series) #63 (Marzo 1988)
- in Spécial Strange (Editions Lug, 1975 series) #57 (juillet 1988) [-1 page]
- in Prosjekt X (Semic, 1990 series) #7/1990 ([august] 1990)
- in Gli Incredibili X-Men (Edizioni Star Comics, 1990 series) #22 (Maggio 1992)
- in Marvel's Greatest Super Battles (Marvel, 1994 series) (July 1994), (July 1994)
- in Sabretooth Classic (Marvel, 1994 series) #9 (January 1995)
- in X-Men Mutant Massacre (Marvel, 1996 series) (October 1996)
- in Essential X-Men (Marvel, 1996 series) #6 ([August] 2005) [black and white]
- in X-Men: Mutant Massacre (Marvel, 2009 series) (2009)
- in X-Men: Mutant Massacre Omnibus (Marvel, 2018 series) (2018)
- in X-Men Milestones: Mutant Massacre (Marvel, 2019 series) (2019)
- in X-Men - La Collection Mutante (Hachette, 2020 series) #5 - Massacre mutant 2ème partie (décembre 2020)
- in Marvel Masterworks: The Uncanny X-Men (Marvel, 2003 series) #14 (2021)
- Keywords
- Morlock tunnels; Mutant Massacre
Continued in Thor (Marvel, 1966 series) #374 and The Uncanny X-Men (Marvel, 1981 series) #213.
- Script
- ?
- Letters
- typeset
Letters from: Jeff Silva, Earl R. Gomersall, Jr., Randolph M. Petilos, Alan Tulay and Scot W. Myers.