blood.png
    Created by FischKopF, source: http://www.quadropolis.us/node/2693
    "Feel free to edit, claim it's yours, use it in own projects"

bullet.png
    leileilol, GPL

snow.png
    Kevin "Hirato Kirata" Meyer (CC-BY-SA)

plasma.png
    Slawomir 'Q009' Blauciak (CC-BY-SA)