My mind instantly went to The Radiance, which is a bad-ass boss in Hollow Knight. I'm not sure what radiant quests are, but I'm assuming they aren't well liked.
Remember in Skyrim after you finished the dark brotherhood quest line when you'd get assassination quests like "Kill the [adjective] [noun] in [random dungeon]" so you'd have something to do after the handwritten quests were all done? That's a radiant quest.