Bradley uses matts computer to order monster blood. But Matt's sister finds it and puts it in Bradleys cereal. Bradley sees her put it in there and switches bowls with Matt. Matt eats the cereal and the Monster blood with it.
Bradley tells Matt about the bowl switching and Matt felt like an idiot for not thinking about the Monster blood that morning. Matt starts to grow and tells bradley to find the antidote. There is no antidote but luckily it was just a 12-hour sample of Monster blood.