This is the premiere issue, but is actually a continuation of the prior series, which ended in October 1973.  This story is continued from Strange Tales #181.  There is a lot to say about this important book!  This book features Adam Warlock donning a new costume.  More importantly, it contains the origin of Magus, it has the 1st cameo appearance of the In-Betweener, and it's the 1st meeting between Thanos and Adam Warlock.  Great cover, artwork, and story by the great Jim Starlin.  This Bronze Age key book is graded 9.4 NM with white pages by CGC.  It's a very nice copy!