The Human Skull is an item in Mario is Missing! It is a fossil depicting a member of the Homo rudolfensis species (and not Homo habilis as the game claims). It gets stolen from its rightful place in the National Museum of Kenya when a bunch of Koopa Troopas cause chaos in Nairobi. It is taken back by Luigi when he travels through the city, but as he does not recognize it, he asks other people within the city about it. All of them recognize its ancient history, and they tell Luigi to return the skull to the museum. He eventually gains enough information to do just that, bringing the Human Skull to the museum's information booth and reopening it to the public.