A Brutality allowed a player to pull off an extraordinarily long and rapid combo to kill an opponent. These combos appeared in Ultimate Mortal Kombat 3 and Mortal Kombat Trilogy before they were dropped, alongside the other forms of finishing moves when Mortal Kombat 4 was released. They were introduced following the release of Killer Instinct in 1994. In the game, there was a finishing move known as an Ultra Combo in which a fighter brutalized an opponent with a tremendous combo of over twenty hits. Mortal Kombat, to possibly outrival their adversaries, incorporated their own form of a deadly combo, known as Brutalities. In doing one step further, Mortal Kombat’s deadly combo-finisher actually killed an opponent, making them explode in a fantastic, bloody fashion.
Brutalities were, however, very difficult to perform. Upon defeating an opponent, “Finish Him” or “Finish Her” would appear on the screen, and the player would then be able to perform a Fatality. To do the Brutality, one had to perform a long combo by quickly pressing an eleven button combination. Even if successful, the Brutality had what was considered a lackluster payoff — the opponent would disappear in an explosion of blood and an unrealistic amount of bones and limbs covering most of the screen. In some versions, the opponent's bones and limbs would simply fly off the screen.
Because of its extreme difficulty to perform and unspectacular results, the Brutality was unpopular. It was dropped after Mortal Kombat Trilogy and not featured in Mortal Kombat 4. Brutalities were brought back for Mortal Kombat: Shaolin Monks in 2005. They were upgraded into a three dimensional environment, were easier to pull off and were more spectacular in comparison to previous games. Here they function as a power-up mode of sorts that lasts until all Fatality orbs are depleted and turns normal attacks into devastating combo assaults, with strong attacks and throws instantly killing the enemy.
Mortal Kombat X
Brutalities make a return in Mortal Kombat X. However, they function in a completely different way compared to previous games, as Brutalities here are now essentially special attacks or combos that go on in a fatal route to kill the opponent outright in a more violent fashion similar to a Fatality. In addition, many of the Brutalities in the game require different criteria to meet, and they can literally be anything such as performing special moves a number of times or the use of interactive objects. However, they all share one thing in common, that being the required special move must be the final hit before the health gauge is completely depleted. But even then, the attack must be delivered under certain circumstances such as hitting them in the head, or even respecting a certain distance before dealing the final blow.
An example of a Brutality being used as a finisher has Quan Chi using his Throw where he forces an opponent into a portal, but instead the usual throw ending, his opponent is ripped apart and their gory remains shower Quan Chi.
Each character has five different listed Brutalities (two universal Brutalities, and three Brutalities exclusive to each Character Variation), with some characters having a sixth or more unlisted Brutality as well, hidden within a character's 3 variations, though some characters had their Hidden Brutality added in certain updates of the game.
In addition, Shinnok can also do Brutalities linked to the moves initiating them that are copied only via his Impostor Variation and by meeting the conditions of another character's Brutality in some circumstances. Kenshi, Kitana, Jacqui, and Takeda can also reflect projectiles with Brutality properties back onto their owners, with Kenshi having to be in his Balanced variation and Kitana in her Royal Storm Variation, and Takeda in his Ronin Variation, with Jacqui's being a universal Brutality. All Character Variation-exclusive Brutalities, except for the characters from the DLC packs (as their Brutalities are unlocked upon downloading them), can be purchased from the Krypt.
In addition, there are also Stage Brutalities, similar to Stage Fatalities, with some Stage Brutalities getting added into the game with certain updates. For example, in the Dead Woods arena, a broken tree stump can be thrown, with the Brutality resulting with the tree stump impaling into the opponent's chest.
After successfully finishing a Brutality, the announcer says "Brutality" as the wording appears in big red words (in a similar font/fashion with the Fatality one), followed by naming the winning character and, if applicable, eventually a "Flawless Victory".
Mortal Kombat 11
In Mortal Kombat 11, each character starts with two Brutalities available. Additional Brutalities must be unlocked in The Krypt or the Towers of Time. In addition, every character shares a universal uppercut Brutality, the Klassic, that knocks the head and spine off of the victim, which can only be done if the winner did not block at any point during the last round. Some Fatalities from the original trilogy also return as Brutalities such as Kabal's Soul Scream and Kitana's Kiss of Death.
- Brutalities were originally set to appear in Mortal Kombat (2011). However, Ed Boon later confirmed via Twitter that the finisher was cut due to time constraints. 
- Brutalities are the only fatal finishing moves available to Rain and Noob Saibot in Ultimate Mortal Kombat 3, other than Stage Fatalities.
- There is a glitch in Mortal Kombat X caused by specific Brutalities - If Jason Voorhees is in his Unstoppable variation and Jason's opponent does a Brutality, when the character does their Post-Brutality victory pose, Jason will sometimes do his Resurrection animation, but the fight will still be considered a win to Jason's opponent. There is a chance of this happening regardless of the damage done to Jason, for example this has a chance of happening even if Jason lost his legs as a result of the Brutality (resulting in Jason floating in mid-air), or even his head.
- Interestingly, in Mortal Kombat X, Fatalities were to be announced in a similar manner to Brutalities in the finished product, as seen in Raiden's trailer against Kotal Kahn, where the "_ality" is announced before the "_ wins!".