Pretty good! The lighting is awesome and so is the environment :D I have a couple suggestions, it would be nice to have a counter for the collected orbs/keys. A great thing you could've done is alternating between destroying orbs and collecting keys (for each orb you destroy, a key spawns and you have to find for the next orb to spawn). This will force the player to switch frequently between the two modes, instead of being stuck in one for a long time. And I also wished I was able to jump xD