Rainbow Comics, Cards & Collectibles is where Sioux Falls stops pretending it doesn't still care about the stuff it loved at twelve. This is a real comic shop — not a gift store with a spinner rack.
Rainbow Comics stocks single-issue comics, collected trades, and graphic novels alongside trading cards, collectibles, and toys that range from current shelf-warmers to the kind of thing you describe to someone and watch their eyes go wide. They pull new releases, maintain back-issue inventory, and carry the card sets that people actually hunt for.
Locals come back because this place takes the hobby seriously without taking itself too seriously. If you're chasing a specific issue or just browsing the kind of shelves that reward time spent, the selection holds up. That's not a small thing in a market where comic shops come and go.