I really liked the art and aesthetics overall, the light mechanic is very clever, tilesets, backgrounds and levels looked really good and the particle effects and lighting were used very well. In all of those regards, the game is perfect, very polished and good looking.
For the gameplay... well, it was quite infuriating sometimes. Respawns are too infrequent for the game's difficulty, the dash direction and wall jumping felt unpredictable at times and I felt constantly slowed down because of the wait time after dashing (which maybe should replenish once you grab a wall or touch the floor), even with the extra one contained in flashes.
I died many times because throwing a flash would freeze the game for a couple seconds and send me into a wall of spikes. A particles slider would have helped prevent the lag spikes (although I can't say anything since my entry suffers from the exact same problem), but considering you almost missed the deadline, I totally get it.
All of that being said, you guys did a great job. This is one of the top games of the jam, for sure.