Lyle in Cube Sector has an interesting concept for a platformer. You fight your enemies using cubes you pick from the ground, later you even learn to use the cubes to make a double or even a multiple jump. You can go anywhere in the game if you want, but some places can only be reached if certain abilities have been gained.
The game seems to be bigger than it really is, since you’ll spend much time exploring every corner of it for HP or skill enhancements. LiCS looks a bit like an old NES game, but like one that is very polished. The plot is negligible, but the gameplay is good (the only thing which is quite annoying is that you don’t start with a full life bar). If you like old-school platformer gameplay, try LiCS.