A Hara-Kiri is an alternate finisher where the losing player would cause their own death by using an input combination similar to performing a Fatality. While the player who's victorious will still win, the Hara-Kiri serves as a method of the losing player to be able to end the match on their terms instead of allowing the winning player the opportunity to finish them off. Hara-Kiri, in Japanese, (腹切) means "disembowelment."
- Noob-Smoke has two Hara-Kiri's, while everyone else has only one.
- Kenshi is the only character in Mortal Kombat: Deception who performs the traditional Hara-Kiri which involves self-disembowelment; while a Hara-Kiri is typically performed with a Tanto, Kenshi will use Sento to perform the Hara-Kiri.
- While the Hara-Kiri was introduced in Mortal Kombat: Deception, there has been suicide-based finishers in other games in the Mortal Kombat series. A few examples of suicide based finishers include; Cyrax's "Self Destruct" Fatality in Mortal Kombat 3 (and all ports), which has Cyrax enter a code into his arm panel and subsequently explode, killing both fighters. One of Raiden's Fatalities in Deception has him releasing a ball of energy and throwing it at his opponent resulting in both of them exploding from the energy burst. In Mortal Kombat 2011, Cyber Sub-Zero has a Fatality where he enters a code into his arm panel and jumps onto his opponent and grabs them, the two freeze and quickly burst into shards of ice. In Mortal Kombat X, Predator has a Brutality where he presses a button on his arm panel before laughing with a timer being heard, ending with both fighters exploding.
- In Mortal Kombat X, in Scorpion's ending he tries to commit hara-kiri, but gets stopped by Raiden who imbues him with a small portion of the Jinsei's power.
- Also in Mortal Kombat X, Kotal Kahn has a Brutality titled Offering, which has the hallmarks of a Hara-Kiri. In it, Kotal does not harm his opponent in any way but will rather commit suicide by cutting his upper torso open, granting victory to his opponent.
- Similarly, in Mortal Kombat 11, Erron Black has a Brutality titled Goodbye Cruel World, which also can qualify as a Hara-Kiri. In it, Erron holds a lit stick of dynamite in his hand until it explodes, blowing off parts of his head and torso.