Amazing Spider-Man #361 has a Carnage cover and is the character's 1st full appearance.  This is a big Copper Age key!  Written by David Michelinie and drawn by Mark Bagley.  Although this book has been highly sought after since its release, it is very popular as of late with all the furor surrounding the new movies.  This book is graded 9.6 NM+ with white pages by CGC.