Marvel released Secret Wars beginning in 1984 so naturally DC's epic response is Crisis on Infinite Earths.  Third issue in the 12-issue limited series.  2nd cameo appearance of the Anti-Monitor.  It has a really cool cover by the late, great George Perez.  Perez also does interior art.  Story by Marv Wolfman.  This Copper Age book is graded 9.6 NM+ with white pages by CGC.