Very nice looking game.
Platforming is very tough here for me. Gave up after >300 deaths when there is no save between two difficult locations both with moving platforms and spikes, the second having disappearing ground platforms. To go through the first location I need near 10 tries each time only to reach the second, and it becomes very costy to try different ways of solving the second.
I understand this complexity is intentional in this kind of game. So, it's just my personal wish it having even more checkpoints in some particular places. E.g. like before chasm with spikes it was very convenient to respawn immediately and try different key combinations.
The most pro of this game is overall presentation. May be only music is a small want.