The pixel art is quite good and the enemy and skill design have potential, but there's work to be done. Movement and jump speed are needlessly slow, the level design is quite spacious, you can afford to speed things up a little. Speaking of level design, it could be more intricate. There's only so much entertainment you can get out of simple platforming and straight paths.

That being said, I like the Shield mechanic and the risk-reward system that comes with knowing when to not use it too soon. It'd be even better if enemies appeared in groups more often.

This game has potential, but it needs some polishing, that's all.