Nice core mechanic, but lacks a bit of meat on the bone. Felt like maybe it could've been a good rhythm game, "Crypt of the NecroDancer" style? Dunno. I won't say it was easy - but I stayed fairly consistent after I understood the mechanics.
Also monsters seem to serve close to no purpose, it seems much better health-wise to just wait til you see a weak enemy or a scroll. Also time refill vials spawn pretty often, so I could top up my time even after ignoring it for a while.
Got a triple grim reaper spawn once, that's where the reroll came in handy, but if I rolled a second triple grim reaper - it would've been unfair. I dunno if you have it purely random or not - but that one thing to consider.
A cute little game, I wish there was a bit more than just selecting a correct tile.