Good Fun
I really liked alot of things about this platformer. It was very nostalgic, I liked the colors, music, and animations. Enemy variety was decent. The gameplay was on the border for me, going from challenging to hard. The story/universe looked interesting as well, even though we only got a peek at it so far.
The jump mechanic was fine for the most part except for the closed in areas where there were spikes, ghosts and turrets all going. I understand the challenge but considering the number of oppurtunites you are given to get hurt, fall, etc, it sometimes felt a bit excessive. Timing some of the jumps required until waiting the last literal second, allowing no room for error (latent jumping).
I couldnt help but notice something you said in another review, about "punishing" the player. I believe games should be fun and challenging, but certainly not frustrating. In order to have challenge there has to be a certain degree of difficulty, but to design the game with "punishment" in mind seems counteractive to a game itself...which is supposed to be fun.
Having said that, this game is pretty good as it is. Just wish the min/max of the jump was a little tweaked. I noticed some of the level design took into account that you expected the player to jump max and float into the ceiling. Since that is counter intuitive to most platformers, you might want to throw that expectation onto one of the ingame signboards, because it makes seemingly impossible jumps possible once considered.
Good Luck on future flashes!