Overall I enjoyed the vibe, the layout was good and felt like a proper metroidvania.
The level design does a good job of leading the player and is engaging, but entering rooms with an enemy walking straight towards you feels really frustrating, especially the part where there are spikes above the slime, you can also get knocked back into the other room which resets the enemy again, IMO the player should be able to survey a room without rushing(unless it's supposed to be an ambush).
In combat I found it to be a little frustrating that the basic slime doesn't get knocked back enough to kill it while it's walking towards you, and you sometimes have to walk back to get the third hit in, since it broke the flow of the 3-cycle attack. Other than that I though the enemy variety was good and they get introduced at a decent rate. i-frames would really help out in hectic moments where you get hit a lot as well