Are there any single boss rush category in the game? (as in only defeating a single boss at godhome, not reaching and defeating it in-game). If not, do you think there'll be an interest in that as a category, if someone's ever to start one?

Patheon IL runs, its under Level Leaderboard. I your talking about indivisual bosses, then no. i think there used to be one but people decided it was too hard to keep track of or smth

i mean technically hiveblood% under the category extensions is a boss rush, but there are no flat out boss rush categories.

They don't exist because most bosses in Godhome are like sub 30s.

I think they'd be cool to have, but kinda unnecessary. Super Meat Boy has ILs for every level and most of them are under 15s.

A big reason we don't have them IIRC was fluke cheese. Flukes have an RNG chance to have hitboxes linger, meaning that there's a lot of bosses you can kill in 3 seconds or less with a good pattern. Even if it's not flukes, there's a lot of other ways to cheese them. Maintaining a leaderboard for such short runs is difficult, especially with the timer variances (even a frame matters when its that short). It's also slightly redundant when we have the pantheon IL's (which use a lot more tasteful methods)