Got to about night 20, didn't take a single point of damage. This was really fun! It didn't quite click that making a rectangle would be more effective than simple reflection around the center, and finding out that worked was a bit of a dopamine hit.
The game felt very easy, and honestly the only sigil worth getting is the sulfur sigil.
The sound was a bit busted because the only available build was HTML, but the particles made up for that.
BTW I really appreciate the alchemy theme :)