For this prank, all you need is some really spicy hot sauce and a bottle of ketchup. Just pour some hot sauce into the ketchup and wait for people to use it they scream trust me ive don it and it works the story behind it is if u have an empty bottle of ketchup then fill with the full bottle of hotsauce then buy more hotsauce and if your mum says when did we buy more ketchup say dad bought it