Mortal Kombat X's Brutalities: Expectation vs. Reality!
Ultimate Mortal Kombat 3 and Mortal Kombat Trilogy introduced the rather difficult to do Brutalities which requires a long sequence of button presses. These were not very popular because of that. In Mortal Kombat Trilogy (which I hope will be a PSN downloadable) had the One Button finisher move cheat which made brutalities easier. They were long combos that made the opponent explode.
In Mortal Kombat Shaolin Monks (an adventure game), the Brutality was re-added as a boost when fighting enemies for later parts of the game. It allowed one to easily clear a room out of enemies and have a super high combo score against the surrounding foes.
In Mortal Kombat X, Brutalities make a return in another form. While I was expecting them to be like the Ultra Combo from Killer Instinct, instead this is where the final blow is thrown against an opponent whose life bar is flashing and there are CERTAIN conditions to be met per character. Above is an example of Liu Kang's Brutality called "Hot Head" which requires two stage interactions during the match and firing an air fireball that hits the head as a final shot.