make it so that you interact with clu he asks for cheese. (in early game there should be a fake cheese and a normal cheese that the player gets) if clu is given the bad cheese he gets angry and vaporizes the area around him, then starts the final boss battle (he is the boss), but if you give him normal cheese he gives you a random best item in the game (1 cheese = 1 item) eventualy he gets angry because it wasnt the right kind of cheese, so the final boss battle is started, but the player gets one of the best items in the game (from giving clu the cheese) to help them. if you beat him he takes a nap, and you can feed him anything, i mean anything. (he basicaly is a trash can if you beat him)
pls add this