A source from Square-Enix has leaked that classic Final Fantasy villains will be popping up as downloadable content for Final Fantasy XIII-2 in the near future.
For example, Gilgamesh from Final Fantasy V at some point will appear as someone to fight in the Coliseum. Defeating him might earn the player a crystal which will allow the player to add him to the monster slot of the party to fight alongside in the game.
The source also revealed that a guest villain from Final Fantasy VI will also be showing up, but wouldn't say who. Possible villains include Kefka, Ultros or Kaiser Dragon.
Final Fantasy XIII's villain Jihl Nabaat had been leaked as an upcoming Coliseum combatant two weeks ago.