Revealing mistake: During the opening scene, a few shots after we see the Outworld ninjas falling through the portal and leaping about, there's a shot of several monks fleeing that tilts up towards the (digitally replaced) sky. As it does this, you can see several hard lines about in the sky from where pieces of the digital animated skies were "stitched together." It's easy to miss the first time, but if you know to look for them, they're pretty obvious. You can see similar lines in the sky in several other shots throughout the scene, but it's most noticeable here.
Revealing mistake: When Liu Kang and Kitana fight Smoke and his goons, Kitana dodges one of the goons and then roundhouse kicks him. It's obvious in the wide shot that her kick did not connect.
Continuity mistake: When Sonya overhead throws Mileena into the ground, she throws her with one arm (she even ends up facing the camera). In the next shot, she's throwing her with both arms.
Chosen answer: The films never address this but in the games Scorpion is an undead revenant and can't really be killed in a conventional sense.
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