Pretty impressive. I like how the healing works in this game and getting hit isn't too punishing. The graphics are nice and the movement is smooth.
The only thing I don't like is the shooting. It's only worth firing at enemies head on. If you try to do it while strafing, it's highly inaccurate. It doesn't even look like the bullets spawn from the weapon.
As a demo, it's quite cool. Only two types of enemies so far but each one has different sprites and animations.