Discord meets Celestia and he realizes that there is a feeling called love. But when something takes over him Celestia is forced to turn him to stone.
1000 years later Discord returns, hoping to make it up to Celestia, but thinks she does not like him anymore. He causes chaos in Ponyville.
When Discord is set free from his stone prison, he thinks that he can finally make it up to Celestia, until he meets Fluttershy. His heart cannot choose, so he causes havoc and chaos again
Discord has to choose Fluttershy or Celestia....