Ultimate is now out, so... enjoy.
A few new things for the newcomers (Spoilers are in effect here)
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Fatality - Rain: He uses his Super Roundhouse to send his foe in the other direction and then shoots out two water jets to leave holes in their head and gut. After a quick Bohemian Rhapsody moment with the other ninjas, he creates two water blades to trisect the foe
Fatality - Mileena: This one is definitely NOT for the squeamish. After she licks her foe with that tongue of hers, she guts her foe with her claws and then going into the wound arm first and grabbing their face... it ends with her ripping their face off AND gutting them through the same hole! Seriously, this borders on some Story of Ricky shit here (Which, coincidentally, I watched earlier. It's absurd as all hell.. I mean, it's a extremely violent kung fu flick).
Friendship - Rambo: Remember laser tag? If you do, Rambo's friendship is him playing laser tag.
Friendship - Rain: You know what works well with water powers? The old carnival game of filling a target with water. He does that, wins and gets a stuffed fish as a prize (the joke here is that he found Nemo)
Arcade Endings
Rambo: After defeating Kronika, Rambo ends up with the Hourglass, but wants nothing to do with it. Deciding the fate of all people? That's not for him. All he wants is to go back home.. which he does
Rain: After defeating Kronika, Rain gets control of the hourglass... yet it doesn't solve the one mystery in his life: The true story of his parents. Turns out that Argus had a bit of a Zeus complex - he liked banging mortal women. He knocked up a woman named Amara and, unbeknownst to Rain, he wasn't abandoned by his mother. Turns out Argus had placed him with peasants in order to conceal what he did. His mother died from the grief.. so, as an act of revenge, he takes out Argus along with Taven and Daegon. He spares Delia as a way to remind her of how his mother felt
Mileena: After defeating Kronika and taking the Hourglass, she takes out Kitana. See, all Mileena wanted was to have a family.. Kitana wanted no part of that, so she had to die. Thanks to the powers of the Hourglass, Mileena is the Kahnum of Time with her parents (Sindel and Shao Kahn) watching over her. She takes pleasure in seeing Jade, Liu Kang and Raiden all bow to her.. yet, she realizes that she will need an heir to her throne. Along with Tanya, Mileena has a new daughter. To her, Mileena isn't an abomination. She is perfection.