I had a sudden and out of the blue idea for either an rpg or top-down adventure game
Basically it would be kind of Paper Mario in presentation, cutesy but still well detailed, with a focus on like toy block (Lego or Megablock or whatever your preferred building block brand is) aesthetic. Some of the main mechanics would be things like editing your weapons or equipment with blocks, both regular kinds and unique ones like a plastic fire or something, to grant additional effects or stats or stuff like that.
I guess it would basically be like Cube World but actually finished and not a third person mmo