I adore the artstyle, but I wasn't a huge fan of the gameplay. I think it was too luck-based and inconsistent. For example I got stuck at the second level for a couple of minutes but then breezed through the third level on the first go by sheer luck. Only way to gather intel about the enemies' paths and whereabouts was dying to them, which was just infuriating. Also the level design was kind of unfocused. There were too many corridors and needless spikes.
Sorry for ranting. You did a great job with the invisible enemy's design. I jumped when it scared me the first time.