Looks pretty good. The artstyle feels fitting.
The game is very short but gives an idea of what the game wants to do.
Minor criticism on the platform gameplay, though. It feels slightly clunky and not quite responsive.
This, I belief, is just a deceptive minor flaw that I trace to two elements:
1. The unresponsive lock when you're running in one direction and then turning, which locks you into the slide.
2. The lack of transition frames from jumping at a stone to making contact with it and pulling up onto the stone.
These two feel unresponsive and lock you out of movement controls.
My suggestions:
1. You already have a really cool turn animation that's meant for exactly what I'm complaining about. But this only occurs when you press the opposite arrow key WHILE pressing the previous arrow key. I'd suggest that you instead check if the opposite direction key is pressed while the sliding state is true and then trigger the turn animation.
Bonus points if you keep track of how long a character is running into one direction and, after a certain time, apply a slight speedup modifier that also extends the slide length when releasing (thereby giving a longer under-the-skirt look). (So the player has a walking motion, a run motion, and a prolonged run that allows long slides)
These two things would make turning and sliding feel a lot smoother in my opinion.
2. You've already created a system for hanging, pulling up, reversing direction when hanging, that's surprisingly robust - though most players likely won't notice during the short gameplay. However the current animation where the character clings to the rock and then lifts up is too slow for the normal gameplay of a platformer. It's locks the player out for too long. It's a cool animation, but I'd only use it for when the hanging character pulls up (as you are currently doing).
For a more fluid connection to the walls, I'd suggest you use the distance of the character to the wall to decide between what happens.
E.g. if the character is far away but the player is pressing the key towards the wall, the character stretches out the arms and barely catches on. (Outstretched Arms -> Into the hanging animation -> (on space press) into the pull up transition.
This "punishes" characters with a delay for barely making the jump.
However if the character is very close to the rock, instead of clinging to it, the character vaults one or two-armed onto the rock, maintaining the momentum.
This change will make the climbing & jumping system more dynamic, reward good jumps with speed & momentum retention and feel more fluid, while clunky jumps and barely reaching somewhere interrupts with the currently existing animation.
But so far, a very promising looking game. I'm curious how you're going to use the turn-away-from-wall-while-hanging animation in the gameplay. I can see some interesting climb & jump sections with that, that use the verticality more than the horizontal to change things up.
EDIT: Also, if you have two different wall-climb animations, one vaulting and one pulling transition, you actually have the leeway to make the pulling transition
slower which gives you more time to pronounce the characters' wiggling ass as he/she struggles to climb up. That would be pretty cute, since the current part is relatively quick and short. You can probably get away with an extension of up to half a second that adds more personality & cuteness to the character pulling themselves up on the rock.
