@coin_artist specified the technical requirements for a puzzle containing a Bitcoin reward, and we discussed how to make it slightly harder for this particular work in her series “The Legend of Satoshi Nakamoto”.
Once we hit on a scheme that we both liked, I provided a verbal description of coloured flames representing six-bit chunks of the private key for a Bitcoin address starting “1FLAMEN6”. @coin_artist painted them around the edge of the painting “TORCHED H34R7S”. We checked them very thoroughly, and then @coin_artist put a high-resolution scan of the painting online for her audience of crypto puzzle trail solvers.
You can read about what happened over the next three years in this article.