Go to the mutliplayer level "Zanzibar" stand in the giant wheel and look at the rock on the left side of the base (the closest one) look at that side of the rock and there will be a guy's head with an abel lincoln beard and tiny horns on the rock. Another one is the rock on the left side of the beach (the one by the palm tree) and it will be on the opposite side onf the direction facing you when you pass into the beach.