I liked it but i didn't feel the increased of ennemies per room with the upgrade, The first area is a bit too green, maybe making the background more dark to better view the frontground. I also found the blue zone needlessly huge, the enemies presences was really small and nothing really threaten you and with how short your attack reach i didn't bother fighting anything. Also after founding the power in the blue zone (the things with the seal i can't remember the exact name) i just coudn't found where to go next so i stop there thinking it was were you have finished. Overall the level was good, the first boss was also fun to fight. The controls also feels nice. I also like the pixel art Nice work