Discord is bored, with the ponies in Ponyville getting used to his practical jokes, he was never found either chaotic or amusing anymore. So he decides that sending three deadly individuals from a war-torn world would be the best thing ever, right?

But one joke goes too far, and it will plunge their land in war. Chaos indeed, but too much chaos can potentially turn Equestria into a scorched land.
(A less than serious Command and Conquer fiction. Make sure you play that mission if you have the game to fully understand the situation.)

EDIT: This is still CnB as you all know of but under a new name, Tiberian Maelstrom.