Really solid game! I thought the shooting felt really nice, and I thought all the art looked really good too. I thought the jump was a little floaty but not too bad. I did have one point where almost got locked out where I jumped up and then fell back down, and just as I did the barrier appeared. After a little bit of fenagling I managed to get myself back through it though so I was able to finish the game.
One thing that does kind of break it, and I'm not if this is intentional or not, but I realized if you throw your grenade and then hit right click again, the grenades will explode immediately and you can throw more. After I realized that and by the time they were fully upgraded and I was throwing three at a time I could pretty much clear the screen with a couple of clicks every time.
Overall though, really fun and atmospheric game with just a couple things to iron out. Great job!