So now I have:
Wand aktWand = (Wand)this.getOneObjectAtOffset(0, 0, Wand.class);
if (BördAufFeld () == true)
{
BördAufnehmen ();
int wandCount = getWorld().getObjects(Wand.class).size();
int randomWand = Greenfoot.getRandomNumber(wandCount);
Object wand = getWorld().getObjects(Wand.class).get(randomWand);
this.getWorld().removeObject(aktWand);
}
No syntax errors but also a wand (wall) is not disappearing...

