The Simpsons making fun of German censorship in The Simpsons: The Game. In one level the player runs through a game-production-place - instead of red blood the player can find a large container with "ACHTUNG BLUT" on it and a green liquid in it. ACHTUNG BLUT means ATTENTION BLOOD. It's a funny gag about the censorship and the green blood in German games. The source shows the whole screenshot.