Tower defense is a great idea. It would be really easy to expand by adding towers, enemies etc. Buying spells is quite unique but good, it would be nice if there was a visual indication you bought something. I also like the turning mechanic of the turrets. I don't see any other negatives, maybe just explain the rules bit more
Interesting powerups, nice dark level, would be nice to know what the blue dots do. Also when you pick them up, they don't come back, and the effect runs out, so you can get stuck (happened to me). Otherwise quite nice, but not sure how to get past one point
Really cool features, like the platforms shining when the correct box is on them, the logic gates and the overall colors textures of the level. Sadly the logic gates were finished before I even started to understand the mechanics, maybe make the combination bit harder so it requires a more moving of the boxes. And a bug: the rightmost box in the colored boxes section couldn't be pushed onto the plate. Other than that, a really nice game.
Really nice wall jump mechanic and the custom energy ball. From the mechanics of this game it's clear it trolls the player. Maybe not having to pick each key again and placing some checkpoint somewhere would make the experience less frustrating. And please no randomly placed spikes at the worst places as possible :D
Removing the platforms after a certain period of time is a great idea. It would be nice if they came back after some time has passed, but the level is still passable after that. When squashing the enemy with a box, it would be nice actually see him get smashed :). And maybe the boss arena could be larger, I died many times by falling down. Also probably a bug, but when I died in the boss arena, my hearts were kept at the amount in which I entered the scene, which was 1/5, so maybe fill them back to full. Other than that, it's a really nice platformer, the visible plants and spikes in dark level are great, and the key picking mechanic as well.
Really love the idea of switching colors. Would maybe recommend lowering the difficulty a bit, or be more forgiving. Maybe making the jumps less absolute precision needed would be nice, as it feels too robust. Also adding the option to see whole level clearly, as it's hard to remember both parts, especially closer to the end, which it makes it more frustrating. Other than that, I absolutely love the main idea and the wall jump, that is a really nice addition.
