With the aid of the thunder god known as Raiden, Earth's mightiest heroes have repelled all invasions from other-worldly forces through a tournament known as Mortal Kombat. Although there has been relative peace for many years, a new threat to Earthrealm has emerged. And this time, the threat of evil has two faces. In an attempt to seize control of the realms, the sorcerers Shang Tsung and Quan Chi have joined forces and are preparing to revive the lost army of the mythological Dragon King. Should they succeed, they will be unstoppable. Once again, Earth's heroes must venture to Outworld and kombat the forces of evil. They must act now. They must stop this Deadly Alliance.
--From the GBA Mortal Kombat: Deadly Alliance instruction manual.