One of my favorite 2D indie platformers. Great level design, tight controls, and excellent music. An all-around amazing game that I've beaten multiple times on both PC and PS4 (as part of a free PSN release). A shame that the PS4 version didn't have the original PC release's music though.

Very challenging with tons of levels too - Light/Dark worlds, time trials, hidden levels/warp zones, multiple playable characters, unique "boss fights", etc. I love this game!