Continuity mistake: When Johnny Cage is fighting Scorpion, and he does his human spear, Johnny runs until he stops at the tree. The spear then catches up, and becomes wrapped around the tree in front of Johnny. When the camera changes view, the spear is just leaning on the tree. The camera changes view again and the spear is wrapped around the tree again. When Scorpion pulls the spear back, it goes straight back, and doesn't unwind around the tree.
Trivia: The autographed photo of Johnny Cage that lands among Scorpion's remains is a reference to Cage's 'Friendship' move from Mortal Kombat 2 (a sort of comedy finisher where after beating your opponent to a bloody pulp you would then make peace with them by giving them a present or putting on a little show instead of killing them). Apparently many fans considered kicking the tar out of somebody and then giving them a signed photo of yourself to be incredibly egotistical, hence why it appears in the movie.
Trivia: Every character that fights in the movie does either two special moves from the games, either one move and one fatality: Johnny Cage does the Shadow Kick to Scorpion, and the nut punch to Goro. Scorpion does the living spear throw to Johnny Cage, and the fire breath fatality to Johnny Cage as well. Sonya does the leg grab move to Kano, and breaks his neck with the leg grab fatality. Liu Kang does the fireball move at Shang Tsung, and also does the bycicle kick at Reptile. SubZero does the ice blast at an OutWorld warrior and also does the ice shatter fatality to that same warrior. Rayden does the teleport, and uses his electricity bolts to stop SubZero and Scorpion from attacking the earth fighters. Shang Tsung does the soul steal fatality, and the morphs into Chan Kang. Reptile turns invisible to sneak attack Liu, and also does the acid spit.
Question: Something that was bugging me, but maybe someone who knows more about guns can help: On Shang Tsung's ship, Sub-Zero freezes & breaks off the front of Sonya's gun. What good does this do? The firing mechanisms are towards the rear of the gun. She could have fired off a shot, just not a second one. Freezing the front only locks the slide, part of the barrel and return spring, right? A round must have been chambered, otherwise it would be really stupid for her to be wielding it the way she does. Sub-Zero was not far away, so the shorter barrel shouldn't be much problem. Sub-Zero wouldn't have been able to freeze the bullet, given how he couldn't' stop that icicle that kills him later.