How do you get tiencha in dbz budokai 2 GameCube?

In Dragon Ball Z: Budokai 2 for the GameCube, you can unlock Tiencha by completing the Dragon World mode. Specifically, you need to finish the "Cell Saga" and then collect all 7 Dragon Balls. After that, you can summon Shenron and wish for Tiencha to unlock him as a playable character.