interesting concept. liked how you worked within the theme. alot of potential. only things i noticed. the sound was a bit loud. you have three conflicting styles in your assets. pixel art player, hand-painted level and vector shapes. Maybe moving forward limited it to one style if you are making this a full game. 

It's not a bad game, but I would somehow change the spikes so they fall slower or have smaller collider, so it's more fair for the player.

I like how you start in some dark cave but then you go higher and there is more and more space, so you really feel like escaping.

The visuals are surprisingly detailed for the short time duration! Good job!
The amount of spikes you throw at us is insame though O.O

This is a fun concept.  Grapple-hooking is a fun way to get around in games, generally.  

I wish there were some offscreen warning for when spikes were going to fall, or some amount of control that the player had over the swinging motion.  Often I felt like I couldn't predict where hazards were, and had no way to play around them. So I had to just take the hit and start at the very beginning of the level

Cool game, I like the art :)