Does anyone have a dark-room grinder? It also needs to be capable of handling spiders. It doesn't need to be a spawner, just a dark room in which mobs can spawn. It also needs to be able to auto-kill them, so, for example, I can go AFK and just let it grind. If you do know where one is, or can make me one, I'd be delighted to purchase it. I'm looking for around 5k.