GOO File:Goo Currency Icon.png (or Ghostly Organofluid Outflow) was the limited time currency available during the Treehouse of Horror XXIV Event. It was accumulated in order to win unique prizes. It was also accumulated in the Community prizes, where all players of The Simpsons: Tapped Out had their GOO counted together. When the Community GOO balance was high enough, unique prizes were won. The highest prize was King Homer's Skyscraper, which required 30 billion GOO. Any user could have contributed, whether logged in or playing anonymously.