P.E.P.P.E.R.

Stepping onto the cosmic stage in the landmark first issue of Brian Michael Bendis and Steve McNiven's Guardians of the Galaxy in 2013 — itself a collector-significant key — P.E.P.P.E.R. is a Modern Age Marvel creation born right at the height of the Marvel Now! initiative. With only a handful of catalog appearances, this is a rare and intriguing figure whose pages are shared with heavy hitters like Iron Man, Gamora, Drax the Destroyer, and Annihilus, placing P.E.P.P.E.R. in genuinely rarefied company. Slim on appearances but rich in pedigree, this is exactly the kind of obscure gem that makes digging through Marvel's cosmic corner so rewarding for dedicated collectors.