The lights are on
Liu Kang - Arcade Machine (MK 3)
So by this point in the series we've accepted that Liu Kang can turn into a dragon. That unexplained metamorphosis pales in comparison to what he's able to do in Mortal Kombat 3. Liu disappears into thin air, and then an arcade cabinet of the first game drops from the sky onto his opponent. He then reappears and poses. So...did he turn into an arcade machine? Does he have to disappear to summon it? Why would the game break the fourth wall in such an odd and overt way?
Jax - Giant Stomp (MK 3)
Jax is a ***...we get it. His arms are made of metal, he can shoot missiles out of them, and he'll rip your arms right off your *** body if you look at him crooked. However, we were apparently spared the details on why he can grow to 300 feet tall. Making Liu's dragon morph seem like a fully plausible event, Jax becomes a giant and squashes his opponent like a bug.
Johnny Cage - Three Head Punch (MK 3)
This one may have originated as a glitch from the original game, but it sure as hell confused fans who didn't know that bit of trivia. Johnny Cage performs his decapitation fatality from the original...and then proceeds to knock two more heads off of the same body.
Cyrax - Self-Destruct (MK 3)
In most tournaments, the objective is to stay active in them until you reach the end. No one informed Cyrax of this, as he regularly finished fights by blowing himself up. Inexplicably, he'd always be back and ready to go as soon as the next fight started.
Kano - Skeleton Pull (MK 3)
I'm no doctor (and apparently neither is Ed Boon), but I'm pretty sure you can't pull someone's ENTIRE SKELETON out of their mouth.
Darrius - Re-arranger (MK: Deception)
In one of the more physically-impossible feats in the entire series, Darrius effortlessly removes just about every limb on his opponent's body and re-attaches them to the wrong wound. Legs come out of necks, arms come out of legs, without any explanation of how they're staying put. After his re-arranging trick, Darrius ponders what to do next before ultimately settling on a simple kick.
Smoke - Blow Up The World (MK 3)
With the exception of Cyrax's self-destruct, almost every Fatality in MK history at least left its performer alive and intact. However, Smoke just goes bonkers in this one and litters the ground with dozens of bombs. Right before they explode, the camera pulls way out to show the Earth shaking. Then...the ENTIRE WORLD blows up. Every combatant, every arena, every semblance of the Mortal Kombat tournament (unless you want to get picky and talk about Outworld) is gone with this one Fatality. And just like Cyrax's finisher, everything returns perfectly in-place in time for the next round.
Sure, some of these Fatalities were nonsensical, but that's all part of what Mortal Kombat great - it never took itself seriously. It happily spit in the face of logic, realism, and its detractors, and you could tell the team at Midway always had a blast making it. Mortal Kombat vs. DC Universe toned the violence down significantly, but here's hoping Boon & Co. are working on another ultra-violent addition to the series.