Shang Tsung:
Make a spike come out of the ground impaling the victim trough the anus and make it come out trough his mouth... Then while the victim is still screaming steal the soul untill nothing more then bones fall of the stake...

Scorpion:
Grabs the victim with one hand up and does with his other hand his hellfire move starting a small campfire underneath the victim untill it catches fire.

He throws the spear into the belly of the victim while he is pulling his spear back the stumach and intestines are attached to it litterly taking the insides out of the victim while this is screaming in agony

Raiden: Teleports into the victim, you can see random lightings coming out of the body and how his blood and guts start to boil, then he starts puking it all out letting smoke come out of the pool of blood while raiden reappears in victory pose.

Reptile- Unzips his pants as the camera cuts to an over the shoulder view(over reptiles shoulder) as reptile begins urinating acid onto the victim as they scream and melt
:D

Kitana: Unsheathes both closed fans from their holding place. One closed fan is tossed up into the air, and as it falls she performs a spinning kick of some sort, kicking the fan in the direction of her opponent who is impaled in the gut. The impaled fighter falls to his or her knees wailing, attempting to pull the fan from their body, paying no attention to the fact that Kitana is approaching. The opponent looks up once Kitana's shadow looms over him or her, at which point it is too late. Kitana opens the fan in her hand and swings its bladed edges across the exposed neck of her victim. This does not decapitate the opponent, but rather slits their throat, blood spewing from the open wound. Kitana lifts her foot and presses it against the opponents chest, kicking him or her onto their back, now dead. She would then go into her victory pose.