Mortal Kombat Deception (Gamecube) - Konquest Mode Kai Side Mission Part 3

When you first start the Earthrealm proper portion (not the village where the game actually begins) you should have spoken to Master Shen (located at E-4) and then Elder Wen (located at D-4). Truth be told, I don't remember if you need to defeat Bo Rai' Cho before or after speaking to them. Continue the story like normal until you reach the part when you train with Baraka in Outworld. When done with his training, pay a visit to Elder Wen (D-4). He'll tell you that you are ready as far as skills go, but now your soul is tainted. Train with Nightwolf (as part of the story like normal) and the return to Elder Wen's hut. He'll tell you that the White Lotus could not wait for your return and instead sent Liu Kang to the MK tournament. Still, says you can be of help by defeating some beast men attacking Earthrealm (they are Tarkatan warriors). Defeat them and speak to Elder Wen once more. Now continue the game as usual until you train with Scorpion and defeat Quan Chi. At that point, return Earthrealm and speak to Kung Lao located at the White Lotus Society temple (C-7). He thinks you are the enemy and a fight/challenge will follow (perform a 10-hit combo). Once he is defeated he will ask you to find Kai in Outworld to see if he can help.