It was a kick to hear Stu playing through AI Dungeon. Clearly it's not ready for prime-time, but it is sometimes fun to sit and explore an Eliza-bot. Procedurally generated stories are fascinating to me, and things which seemed impossible when I first started using computers are commonplace now, so who knows? Is it so difficult to imagine an AI-driven game after enough source material is applied to a well-defined parser?
Deities: I'm happy that @Stu still remembers the Halfworld campaign from our college days in such detail. One thing I try to maintain with summoning demons is that they're consistently a Faustian bargain. The creatures are also not native to our plane, so the rule of invasive, predatory species also applies.
I'm also fond of @Tappy 's plan to have a deity's aspect become prevalent in the world while they're walking on it. If the god of WAR is on the planet, not only are warlike solutions in place for nations, it could also be applied to just about any place where turf is in contest. Same for the gods of deceit, lust, gluttony, etc.