I beat the game(minus level 3) with a controller.
Visuals: Look good, a solid pixel art aesthetic. The character and enemy design are fine, just a bit generic feeling though.
Gameplay: Took a hot minute to acclimate to the jump and claw, but towards the end it started to feel more natural to do the timing. The jump reminded me a lot of La Mulana, mostly a dedicated jump but with a little leeway to go back if you messed up. I will say the difficulty curve seems a little high, might be worth adding some more buildup to the mechanics to get the player used to the platforming. I would also recommend adding checkpoints of some kind, though I may just be babied from having per-room checkpoints in other indie precision platformers.
Sound: SFX was fine, though it felt very sad and empty without some music.
Weirdness: Turning fullscreen on then off kept the UI at the fullscreen size, I fixed it by closing then reopening. I mainly switched to controller since I thought keyboard was broken when pressing ENTER stopped working at several points. Though looking at the other comment it looks like it changed to A for some reason and I didn't realize it.