annoying controls, feels like sliding on ice, neat ost and level design and overall great pace and variety. Not bad for an indie platformer

Feels like jumping on ice

You play as a square that can jump and wall-jump. You are avoiding spikes with little variations. You "die" in one hit and restart the level. Most levels will have one to five keys spread about which you need to collect to open the door that ends the level. There is a level select that lets you go back to any previously beaten levels, but they're just numbered so it would be hard to remember any levels you particularly liked.

+ The background music is nice to listen to. It is calming while playing through the difficult challenges.
+ There are optional collectables in the shape of Japanese letters. Each one pops an individual achievement (see the 150+ achievements) and is permanently collected, even if you die mid-level.

- The movement feels too slippery, like I'm on ice all the time.
- I think some of the levels are too long for not having checkpoints. It is frustrating to have a level with a long series of easy platforming sections end with a difficult section that you can't retry quickly because you have to redo all the easy parts first.
- The jump is a set height, no variation, which doesn't sound too bad but I think it is this way because of how the wall-jump is implemented. The wall-jump was a little tricky to understand but the way it works is that when you are against a wall, you slowly slide down it. If you press jump, you will jump away from the wall. You are forced in that direction for as long as you hold the jump button. If you release the jump button, you can press back in the direction of the wall. So if you just tap the jump button, you will jump the full height and can move in any direction. It sounds to me like this was not a necessary restriction. Megaman X's wall jump is simpler to do and this game effectively does the same thing with a bigger learning curve. So overall, I think this jump is poorly designed.
- The spikes have rectangle-shaped collision boxes, so you can't just barely scrape by them. If your box intersects with their box anywhere, you're dead. I would prefer it if the spike collision boxes matched their shapes.

There is more that I dislike than what I like so I can't recommend it. I got to level 26 out of 30 and I'm not sure yet if I'll go back and finish it.