Mortal Kombat: Unchained is the PlayStation Portable version of Mortal Kombat: Deception. The game was released on November 13, 2006, and includes the previously GameCube-exclusive characters Shao Kahn and Goro. It also adds to the roster Kitana, Jax, Frost and Blaze, who were previously unplayable and only found in Konquest mode. Unlike the previous iterations of the game, all of the characters, as well as the stages, are available from the outset, thus no longer requiring the need to unlocking them, though alternate costumes still need to be unlocked.
- Blaze – An Outworld elemental who was captured to incubate the means of Onaga's return, but is now free to pursue his own quest: to monitor the realms' companions and prepare for Armageddon, should they grow too powerful.
- Frost – Sub-Zero's traitorous disciple student who revived after her own freezing ability appeared to kill her.
- Jax – Soldier of the Outer World Investigation Agency who fell in battle, and revived to serve Onaga.
- Kitana – Princess of Edenia who was thought to be killed in battle and revived to serve Onaga; appears to be fully aware - if not in control of her actions.
An Endurance mode was an exclusive new feature in the PSP version, where players can compete against a constant wave of opponents. Also, the PSP's Wireless Ad-hoc functionality could be used for Multiplayer games.
- This is the first game to be ported onto a Sony portable platform, the second being Mortal Kombat (2011), which was ported onto the PlayStation Vita.
- In the character select screen, while highlighting Tanya who is located on the main middle right, the player can press right to move the highlighter down to Shujinko, who is on the main bottom left.
- Except for Armageddon, this is the only game to have all the female ninjas (excluding Khameleon, since she only appeared in Nintendo ports of the series). In addition, again excluding Armageddon (which had all the characters present), it has the most female fighters of any game in the series, with 9 in total.
- Unlike most characters, Kitana, Frost and Jax already have their alternate costumes unlocked. Also, they only have one Fatality, but no Hara-Kiri, due to the fact they were mostly unaltered from their previous forms in Deadly Alliance, only adding the sweep kicks and uppercuts while removing the Powerups.
- Blaze does not have an alternate costume, finisher or weapon in this game.