The Biohazard Tower is a limited time decoration released on November 4, 2015, during the Treehouse of Horror XXVI Event. It's craftable throughout the act three. The Much Apu About Something Promotional update also animated the tower: The bar at the top rotates and emits flashing light and the orange light on the side flashes in sync with the Biohazard Wall. There are no tasks/jobs/quests associated with the tower.