On The Edge Of Death

Fighting an elemental zombie invasion, you're on the edge of death - how long will you survive?

Using Water, Fire and Grass spells as your only weapons, you must shoot the corresponding zombie in order to kill it.

Dev note - This is my first completed project, I know it isn't the best and a little buggy but I'm super proud of what I've made so please be nice :). 

Any constructive feedback will be appreciated as I hope to grow with this project.