This reminded me of NES and SNES era games with the art, music, and difficulty. It was definitely a challenging game, but it did not feel unreasonably difficult, nor did the difficulty level feel wrong. I really enjoyed the retro feel of the art and sound. The animations looked great and did a good job conveying information to the player. I was particularly fond of the way the jump looked different based on how long you held down the jump button. The starting cutsceen was a nice touch and helped set the feel of the game.
The controls felt pretty good, though I did find myself wanting to push space to jump instead of z a few times. I thought it was neat that you pushed left or right start moving in that direction and pushed down to stop, while how long you held z affected the height/distance of your jump. I also liked that your jump was based on your movement, so jumping from standing still meant you jumped straight up instead of the direction you were facing.
I didn’t make it very far, but that speaks more to my skill level than to the quality of the game. The check points did help me get farther than I might otherwise have, and I enjoyed it enough that it makes me want to play more to improve so that I can try to make it to the end.