also a good RPG with some betting options to get extra equipment, skills, etc. may be a good go. Seen so far a couple of ideas (e.g., based on game of thrones series), but they were still not good enough. It requires however substantial preparation of the story.
Dragon's Tale is a RPG with
BTC but not really anything with battling or equipment.
I still haven't played it, but from the descriptions I've read so far, as well as from what I've seen of others' comments, I'd say Dragon's Tale is just a glorified casino; not so much an RPG, unfortunately.
But it could be interesting to play an RPG where you could use BTC to pay for items and equipment, and withdraw any winnings made during the game, be it from selling things, killing mobs, killing other players, or whatever.