That was a really big (and long, cause I died a lot) game. I'm surprised you managed to do all this in a month. I was honestly expecting something else. I don't know what, butcertainly not the megaman 2 blocks from hell again.
Graphics are mostly consistent. The artstyle's simple, but the lighting and effects make it shine. There are some issues with visibility and readability, though, but nothing serious. Though, I wasn't sure what floors killed you at first. I don't even know if they're electrified or just spikes or something else entirely.
Collisions are a bit wonky. A smaller hurtbox than the characters (separating collision box from hurt box) would punish the player a little less. The grappling hook click sometimes didn't register for me, but that may be me.
I really liked the music. The sound effects are weird.
Overall I liked it. It was harder than what I was expecting, but that's on me.