Harpoon first appeared in Uncanny X-Men #210 (October 1986), and was created by Chris Claremont, John Romita, Jr. and Dan Green.

[1][2][a] The team ambush a Morlock girl named Tommy and a human Hellfire Club soldier called Richard in Los Angeles.

[4] In other appearances during the crossover, he crosses paths with Cyclops, Beast and Iceman, and tries to kill a Morlock named Plague with Sabertooth, but they are stopped by Apocalypse, who recruits the woman to his Horsemen.

[volume & issue needed] Harpoon is thought to have been slain during the Inferno incident, but as often shown, Mister Sinister can clone his Marauders and bring them back at any time.

He begs her that he wants to just surrender but unemotionally, Rogue hits him away from her; Morph shape changes into a wall to stop the soldier's pace and keep him from ending up in the Pacific Ocean.

[citation needed] This version is a member of Mister Sinister's Marauders who is captured by the X-Men, who interrogate him for information on the missing Jean Grey before transferring him to the Mutant Response Division's custody.