Tuska inks per Nick Caputo. Original indexer credited John Verpoorten. Sources for lettering credits are The Marvel Comics Index (Olshevsky 1981), The Official Marvel Index to the X-Men (Olshevsky 1987), The Official Marvel Index to the X-Men (Ward 1994), and Official Index to the Marvel Universe (Vandal et al. 2009).
The caption in the final panel in the original version of this story, from X-Men #45, says, "You'll find the cataclysmic conclusion of this two-part thriller in Avengers #53! On sale now!" In the reprinted version from X-Men #93 the caption says, "You'll find the cataclysmic conclusion of this two-part thriller in Giant-Size X-Men #1". Apparently Giant-Size X-Men #1, on sale the month following X-Men #93 (cover date of GSXM #1 is May 1975), was originally supposed to include a reprint Avengers #53. However, there was a change of plans, and instead Giant-Size X-Men #1 featured a new story which introduced a new team of X-Men. The new X-Men adventures continued in X-Men #94. #93 was the last reprint issue, and Avengers #53 was not reprinted until three years later, in 1978, when both X-Men #45 and Avengers #53 were reprinted in Marvel Triple Action #s 45 and 46.
Updated data information from James Serpas (July 6, 2005) and Tom Hartley (June 8, 2011).
Writer, penciler and inker credit from printed credits of comic.
Splash page is signed, "Stan Lee & S. Ditko".