Hey, Redigit! Just want to say hi! Second of all, I've been working on this NPC for 1.3.6. It could be called the Hellspawn. It's friendly, though. I posted the same message, except with a typo. So it can be found after entering Hell. It only appears in Encased Hellstone. When broken, it could release a Hellspawn NPC. The picture of my NPC idea is in my Google+ account.