Good game with even better visuals, but thats not what im here for so lets talk mechanics. The use eof light and shadows is great, the level plays with the players paranoia of being unsure what is solid ground; many times this errs on the side of bad level design (like telling you to take a leap of faith and getting spikes) but most often there are marks or enemies to show you where to step.
Onto enemies, i started loving them, showing their eyes in the dark is a good merge of visuals informing design, but as time passed i starting detesting them, the hitbox are really bad, many times i get killed if im not perfectly in the center of the enemy and in a long level it makes it unfair.
Onto the level now, this has me split, long levels, no checkpoints and instadeath are usually a recipe for disaster and adding leaps of faith that get you killed to the mix it made me rage more than once, on the other side of the coin it makes good use of the mechanics and tricks the players expectations in good ways, knowing that youll have to go back with little to no light is fun.
Theme, it does the one light at a time thing.
Originality, the one light at a time is done a lot, even more frequent in 2d platformers but being also switches is interesting and the innovation comes on the tight level design.