Gave it a whirl, got to level 5 (Grasshoppers) but couldn't get past that after a couple tries.
Plays well! Mouse control worked great. Very good clarity and distinctiveness on the enemy types. I liked that it auto-paused when I accidentally clicked off of it, life-saving feature, lol.
If it was trying to do anything new with the genre, I either missed it or didn't reach it.
Had a weird bug once where I came back to life (with one health) after I died, and could keep playing underneath the death dialog box. I then died (hard to dodge lol), came back to life again, and died a final time. Couldn't replicate. No idea what that was about.
I think the game would benefit from some sort of health indicators, both on pud enemies and the player avatar, better indicator of when you get hit, something that makes it clear where the player's hit box really is, and maybe a less noisy initial background (sometimes hard to pick out the shots).