I had some trouble with the visual cues early on. It was difficult to spot the gaps I needed to jump, and especially the walls meant for sliding. The wall-slide mechanic definitely needs a clearer indicator.

Regarding physics, I felt the game is missing some Coyote Time. Currently, if the character is too close to the edge, the jump loses its momentum, making it nearly impossible to clear the gap.

Lastly, the toxin mechanic feels a bit too punishing. Releasing it on the lower floor immediately after the player jumps up doesn't leave much room for error. Adding a slight delay before the floor becomes fully inaccessible would give players more time to read the upper levels and plan their route.

I did not get far. I couldn't quite get the timing for jumping over the holes on the same level. I kept hitting my head on the roof above and falling short or being too late and falling into the hole. I think my issue was that I was just trying to jump alone. When I tried doing sprint jumps it helped, though my timing was still not great. My top score was only 23. I like that the controls are shown as you need them, but with the quick pace they can be hard to read and react in time the first time through. It also would help if perhaps you had a mention of sprint jumping, as  I missed it until doing one more play as I wrote this. I think part of it is that you don't really need the sprint initially, so I focused on the jump and mainly ignored the sprint, treating them as separate things. For the attack instructions it says it is also to "slide", rather than "attack", or perhaps "swing".

The biggest thing to me is that you have to use the mouse to click on Replay, when the rest of the game is keyboard. It would be nice if you had the button grab focus, possibly after a short delay to allow the player to stop pressing any gameplay keys.