There’s a Wormverse TTRPG written by Wildbow (technically still in-progress but popular as-is), a Wormverse story done on a forum by Wildbow (kind of like HS), a few Worm MtG cards made by Wildbow and more by fans, and fan-made material for D&D (some of which you’ve seen – capes converted to spells), CAH, SotM, Savage Worlds, Hearthstone…

Sounds like both Wildbow and the fandom have been busy bees!