Billy is an antonigist in Abandoned Discovery Island 3.0
He appears to be a greyscale verison of Donald Duck, with a hat, gloves and looks like a captain.
Billy starts in the Roof, coming out of the chimney first. Then he comes to Character Prep 1, along with Photo Negative Mickey and Disembodied. Then he moves to the Staff Area, Meat Freezer and then the office. The player must shut off a camera to survive.
Having Billy and Eustace in the office at the same time will cause a deep laugh to play and then the game will crash.