The Spit Pit

Story: Mutant alpacas have enslaved humanity with their newfound ability to create fearsome creatures out of their spit.  You play as one of the enslaved humans, doomed to fight an increasingly difficult onslaught of spit monsters.

WEBGL MAY DISABLE MOVEMENT, REFRESH TO FIX

Gameplay notes:
Your attacks have a short cooldown 
You have more than one hit point

WASD to move
LMB to attack
Aim with the mouse

[There's a hidden button somewhere in menus before starting the game]