I was at Goodwill looking for items with usable motors when I came across a dentistry water pick!
This is a water pick:
Gladly paid $2 for it and went home.
I cut it open to reveal the intake hose for the water supply, and attached it to a large jug for less refills.
Put it all together, sprayed it black, plugged it into a motion sensor and voila! Sprays either heavy droplets or a light mist, Works great!
Now I just need to build a corpse to go over it.