Episode Title:The Terrible ThunderLizards / TTL: Birth of a Notion.Episode Description:Scooter proclaims today as Bill's burpday. To Bill's surprise Babs is joining them, but she wants them to build a mall. Meanwhile the Thunderlizards spy on the humans to find out how their explosives are made. The burpday is cut short when Bill and Scooter accidentally destroy Babs' mall.