I got stuck in a few places and had to restart. Not a big fan of the controls either, would be cool to have other options. Good job though. 

A very neat concept! For the first little while, though, I was confused. I didn't realize that "melee attack" meant taking over an enemy. It took until the first boss arena for me to realize this was how to combat enemies. Movement feels nice, but the controls are not really what I'd expect. I naturally went to use the arrow keys to move, but quickly swapped to WASD when I realized I had to use JKL for actions. 

A few in game explanations would go a very long way. Potential!

A bit rough around the edges that could do with further refinement but what's here is a decent basis.

The for graphics are a simple yet clean monochrome style which works for the overall game and helps give it a bit of charm.

All the core upgrades are there, double jump, wall climb and dash. I'd just recommend easing off on the gravity a little as the high fall speed makes it feel a bit clunky to make some of the more precise jumps.

The enemy possessing is also an interesting idea with a lot of potential, though it could do with more feedback on how you take enemies over. I think you press J when next to an enemy but its hard to tell as there's no animation.

So overall, not a bad prototype. Some work here and there and it could certainly become something.

That's an interesting choice of main character.

I love the idea of taking over enemies! I really wish there was more feedback though since sometimes it was hard to tell that I was taking damage. The art style was also really interesting! I hope you guys keep working on this because it's really cool.