That was fun! Very simple, easy to pick up, and absolutely adorable. The music had a great mystical dungeon crawling vibe- very Zelda-esque.
I would have maybe placed the spikes more sporadically throughout the tiles, making them a bit higher of a threat.
I think a small bug was that I got one or two crystals on my first run, died, and on the second I only gathered 2 before the passage opened.
Overall a fun little game, the mouse controlled sword was hilarious to swat away with.