The first episode of Season 6. (You can add whatever you think to it)
In this episode the Puffs, Ruffs, Punks, and Shines had misunderstood what the entire city is trying to do. The city is throwing a huge party for the kids. All the villians had made a truce just for this event, including HIM. The entire city pitches in to make the city a big party city. But, the kids misunderstood what they were doing, they thought they were going to make new versions of them. So, they all teamed up and went to destroying their creator's labs.