In Mortal Kombat II, Mileena is revealed to be Princess Kitana’s evil twin. She was created by Shang Tsung’s sorcery using Tarkatan traits, making her a deliberately unstable duplicate of Kitana.
Mileena serves Shao Kahn and is positioned as a rival to Kitana. Her most recognizable visual feature is the Tarkatan mouth filled with sharp teeth, which distinguishes her from the otherwise nearly identical royal assassin.
Mileena is sometimes described simply as Kitana’s clone, but the story gives her a more specific origin involving Tarkatan DNA or essence. Jade is Kitana’s friend, while Sindel is her biological mother in the main series continuity; neither is Kitana’s duplicate.