let's just pretend and assume they used regular fatalities
or character specific ones
SCORPION pulls off his mask, revealing his flaming skull head. He then breathes fire over his opponent, burning them alive. This is, of course, his signature "Toasty" fatality.
SUB-ZERO freezes his opponent completely, then pulls of their head, takes a few steps back, then hurls it at them, causing their whole body to shatter. One of his Deception fatalities.
REPTILE lashes out at his opponent's head with his tongue. After much tugging, he rips it off and eats it. Classic fatality.
RAIN performs a series of powerful uppercuts which causes his opponent's body to break apart and be sent flying.
ERMAC uses his powers to lift his opponent up onto the ground and slam them on the ground. He does this three times until they explode. Classic fatality.
CHAMELEON turns invisible, then, whilst in this state, rips his opponent's torso clean off.
NOOB SAIBOT grabs hold of his opponent's head and, with much tugging, rips it clean off with the spine still attached. A classic fatality from when he was still Sub-Zero.
SMOKE activates a device on his wrist, then plunges his hand deep into his opponent's body. The device is a "self-Destruct" device and, eventually, both Smoke and his opponent explode.
CYRAX opens his chest compartment and a large grabber comes out. It grabs his opponent's head and slams them onto the ground three times before pulling them back into his body, where they are torn apart. Cyrax then spits out the remains. His Deadly Alliance fatality.
SEKTOR activates his flamethrower and burns his opponent alive. Just to make sure, he steps on their charred head, crumbling it to dust.
STRYKER pulls out his tazer, stabs his opponent with it and repeatedly shocks them until they fall over, dead. Classic fatality.
KABAL takes one of his hookswords, then slashes it vertically down the middle of his opponent until about midway. He then takes his second hooksword and slashes at them horizontally, right where the first is. As a result, the victim's body breaks into three pieces.
DAIROU tears out two of his opponent's ribs and stabs them in the eyes with them. One of his Deception fatalities.
JAREK rips out his opponent's heart, then proceeds to tear out a few more major organs before kicking them to the ground. Based on Kano's Deadly Alliance fatality.
DARRIUS grabs his opponent's arms and rips them off. He then beats them with their own arms until their head is knocked off. One of his Deception fatalities.
REIKO pulls out several shurikens and hurls them at his opponent. For added insult, he walks up to them and stabs one more in their head.
FUJIN creates a large tornado which starts to suck his opponent in. They struggle for a while, but eventually their arms are ripped off and they are sucked into the tornado, whereby they are ripped to pieces.
BO RAI CHO knocks his opponent over, then jumps on top of their head, squashing it. For added insult, he farts whilst sitting on top of them.
MAVADO takes out one of his hookswords, then attaches it to one of his grappling hooks. He then sets it all up in front of his opponent, pulls it back, then lets it go. The hooksword is propelled into the opponent.
HOTARU kicks his opponent to the ground, then proceeds to twist their neck by a whole 540 degrees. One of his Deception fatalities.
NIGHTWOLF pulls out one of his tomahawks and cleanly cuts his opponent's head off. As it flies through the air, he throws the tomahawk at it, cutting it in half.
MOKAP kicks his opponent hard in the back, then proceeds to break their arms, legs and neck into VERY unnatural positions. Based on one of Liu Kang's Shaolin Monks fatalities.
JOHNNY CAGE performs a powerful uppercut, knocking his opponent's head off. Classic fatality.
KANO fires his laser eye at his opponent's head. He then jerks his head down, slicing the opponent clean in two.
JAX squashes his opponent's head with a powerful hand-clap. Classic fatality.
KAI impales his opponent with the staff Raiden had given him and holds them aloft. Powerful forces seep through the staff and eventually the opponent explodes.
SHUJINKO takes out his swords and performs several violent slashes on his opponent's body. He then kicks them in the torso, the slashes causing his victim to fall apart.
KENSHI uses his psychic powers to mess about with his opponent's body, twisting their arms, legs and head into numerous unnatural positions before letting them fall to the ground. Largely based on his Deadly Alliance fatality, but without the eyes coming out.
HSU HAO kneels down and fires his laser at his opponent's body. Eventually, after several seconds of this, the top half of the opponent's body explodes and the lower half falls to the ground.
KOBRA turns his opponent around and plunges his hand through their back. After much pulling, he extracts their entire skeleton, leaving what is left of his opponent to slump onto the ground. Based on Sub-Zero's Deadly Alliance fatality.
LIU KANG morphs into a large dragon. This frightens his opponent and they try to run away, but Liu Kang is able to eat the top half of their body before they can escape. Classic fatality.
KUNG LAO throws his hat at his opponent's face, where it gets lodged. He goes over and pulls it out, then cuts their head off with it.
SHANG TSUNG grabs hold of his opponent's neck and begins to suck their soul from right out of their body. Once he has retrieved as much soul as he can, Shang Tsung then breaks his opponent's neck, whereby the rest of the soul escapes and is consumed.
QUAN CHI leaps onto his opponent's shoulders, grabs their neck and stretches it to a giraffe-like length. Once he has done this, he plunges his hand into the outstretched neck and rips out their spinal chord, which causes the neck to collapse on itself. A (hopefully cooler) variation of his Deadly Alliance fatality.
SHINNOK disappears and two large skeleton hands appear in his place. They grab the opponent and forcefully rip them apart.
RAIDEN grabs hold of his opponent by the neck and begins to electrocute them. Eventually, they explode.
SONYA blows a kiss at her opponent, which hits them and causes them to burst into flame. Her classic Kiss of Death fatality.
KITANA kisses her opponent on the cheek. The opponent suddenly begins to expand and stretch at violent intervals before they suddenly explode. Her classic Kiss of Death fatality.
MILEENA tears off her veil, revealing her dagger like teeth. She then leaps onto her opponent, tears their head off and eats it whilst the body collapses. At the end, she spits out the remains of the skull.
JADE impales her opponent in the chest with her staff, then holds it upright in a vertical position. Her opponent slowly slides down it, whilst their heart remains at the top of the staff.
ASHRAH takes out her voodoo doll and effectively folds it in half. Her opponent does exactly the same back-breaking thing.
LI MEI powerfully kicks her opponent's head off, causing it to go flying into the air. She looks up into the sky, as if wondering where it went, then steps away as the head comes back down. It hits the body with enough force to cause her opponent to explode.
TANYA kicks her opponent in the stomach, causing them to collapse onto the ground. Whilst in this position, she stomps on their back with enough force to blow their head off.
FROST freezes her opponent completely, then kicks the upper part of their body, causing it to break off and hit the ground, whereby it is shattered. Her Deadly Alliance fatality.
SINDEL screams loudly at her opponent, which causes their limbs to be ripped off. Eventually, their body explodes.
NITARA jumps on top of her opponent and begins to suck out their blood. She stops after a while to spit out some excess before she resumes her feeding. Eventually, she kicks them away. Her Deadly Alliance fatality.
KIRA plunges one of her daggers deep into her opponent's forehead. She attempts to tear it out and ends up ripping off their head. She plunges her other dagger into their chest, just to be sure.
SAREENA grabs her opponent by the head and behinds to pull at it. Eventually, their head is ripped apart, leaving her to be holding their skull and lower jaw, the latter of which she forces into their chest.
SHEEVA roars loudly, then begins to pound her opponent into the ground until only their head is sticking out. Her MK3 fatality.
BARAKA extends his blades and impales his opponent with them. He twists their body into several positions by moving his arms, before violently kicking them off.
MOTARO grabs hold of his opponent's torso and rips it off. He then turns it upside down and plunges it, head first, back into the lower part of their body, whereby they collapse.
HAVIK rips off his opponent's leg and with a powerful swing, knocks their head off. One of his Deception fatalities.
DRAHMIN smashes his opponent's head with his club. He hits them a second time to knock them to the floor. His Deadly Alliance fatality.
MOLOCH spins his ball above his head like a large bolus. Once it has gotten to a frightenly high speed, he swings it forward, smashing his opponent to pieces.
SHAO KAHN takes out his hammer and smashes his opponent into the ground. He then swings his hammer like a golf club and knocks their head off. One of his Unchained fatalities.
GORO grabs his opponent by the arms and legs, one in each hand, and slowly begins to pull them apart. Their body explodes violently, and Goro throws the limbs down in celebration. One of his Unchained fatalities.
KINTARO takes out four daggers and violently impales them into his opponent's chest. He then takes out one of these and replaces it in the opponent's head. Based on one of Goro's Unchained fatalities.
ONAGA kicks his opponent to the ground, then flies off the screen. The opponent struggles to recover, only for Onaga to suddenly land on top of them, smashing their body into pieces.