Games

Mileena was magically created by Shao Kahn's sorcerers to be Kitana's "twin" sister. She was not only one of Shao Kahn's personal assassins, but she was also tasked with keeping an eye on her "sister." Although Mileena was always jealous of Kitana's beauty and wanted her birthright for her own.

When Kitana discovered the truth about her parents, Shao Kahn feared for the worst and sent Mileena to spy on her. She discovered that Kitana was conspiring with the Earth warriors and attacked her, in which she died.

She descended t othe Netherealm where Shinnok rules. When Shao Kahn tried to resurrect her, Shinnok allowed her to leave with the ability to read Kitana's thoughts. After Shao Kahn's invasion failed, Shinnok summoned her back to the Netherealm.

During Shinnok's assault on the Heavens, Shinnok resurrected Mileena in return for her aid. She used this opportunity to attack Kitana and prove her superiority, however she was defeated and locked in an Edenian dungeon.

When Onaga returned, Baraka freed Mileena and Onaga ordered her to take the place of her deceased sister and control her armies, even fooling the remaining Earth warriors. Taking her own actions, she stormed Shao Kahn's fortress and took it over. However her rule over Outworld was short-lived as Shao Kahn, Shang Tsung, and Goro stormed the fortress. Mileena surrendered and Shao Kahn sent her to retrieve Shujunko in hopes of using him to gain Onaga as an ally.

Comics

She always wanted to be pretty.Shao Kahn offered a beuty for her instead of her service for him.He gave her a look of kitana.She tryed to kill original Kung lao,but she felt in love with him.She failed in her task.Shao Kahn wanted revenge and he removed her face.She has big and horiblle tooths in her mouth now.Thats way she is wearing a mask.