Hi, thanks for playing our game! :D
Yeah, I can see why the pixel shader is annoying. It's a combination of downscaling and pixelating the image. We did that as sort of a quick and dirty way to save on performance, since proper optimization wasn't going to be a thing because of time constraints.
Your health is actually indicated by the dice in the top left! You have 3 HP, and when an enemy damages you, you lose a dice, therefore lose 1 HP. If you kill the enemy which stole your dice, you get it back. That's indicated by the pink laser going through the enemy.
Yes, the name kind of is a reference to daikatana :D