itch.io

I don't think there's any intended "lowest stone" solution. It's something we'll have to solve ourselves

I fully believe you because I've beaten all of them you said you did. 23 can actually be done if you just loop a single pattern, 13 and 17 I haven't even found a "2 Path Clear" (you use one Aratron stone to activate the other two, it's technically 2 demon but also not?) for those two, like NuSan has 10 and 12.
I uploaded a video of all my 2 demon setups if you're interested in seeing what I did, but I'd love to see your own screenshots too. You could've found fewer stone/fewer step setups. Hit me up on Discord or smth so it's easier if you wanna! (@holoknight)

I've been trying to beat every level with only 2! You also seem to do Level 6 more optimally than me. :p We should get in touch and see if the whole game can be done with only 2 demons or smth

Madman

Can vouch, it's a really fun game to run. I've been doing speedruns since November 2020, and hold the Any% record at 5 minutes 37 seconds. (Build a boat and escape.) Someone else managed to get a 5 minute 59 second time for killing the boss (Which we call Boss Kill%, go figure), which I think's way more impressive. Both categories are fun to just pick up and run every day for an hour or so, and seeing your time go lower feels so satisfying for this game in particular.

Also, really fun to read your adventures while browsing comments for this game. Sounded like it was almost as fun to write as it was to play through.