Those are the levels I dindn't manage to do with only 2 demons:
10, 12, 13, 17, 23
And of those I think 10, 17 and 23 are impossible to be done with only 2 demons (for 12 and 13 I won't make any affirmation but they most likely aren't solvable with 2 demons too).
If you want I have screenshot of each level I solved using only 2 demons to prove my claims.
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)
