Guardians of the Galaxy #18

Set in Marvel's 31st century, this November 1991 issue pits the Guardians of the Galaxy against a startling array of Punisher legacy warriors — the cover by Jim Valentino and Tom Morgan depicts a whole army of skull-insignia-wearing fighters, led by a grizzled elder Punisher armed to the teeth, bearing down on the Guardians. Vance Astro with his Captain America-style shield, Starhawk, Martinex, and a flame-wielding Guardian hold their ground in the foreground, outnumbered but clearly not outmatched. It's a genuinely striking clash of Marvel's future heroes against a franchise of vengeance, and the story title "Punished" makes the stakes feel delightfully ominous.