Continuity mistake: When Kung Lao and Shang Tsung are preparing to fight each other at the tournament, watch Shao Kahn. He gets up off his throne, then it cuts to wide shot and he's sitting down again. Then it shows him standing up again only to go back to sitting down a fraction of a second later. (00:03:40)
Continuity mistake: When Shang Tsung transports the scorpion we see it enter a fire coloured portal in Outworld which then changes to a blue coloured portal on Earth Realm. In all other episodes the portals in the Earth Realm are fire coloured and the ones from Outworld are blue.
Noob Saibot - S1-E6
Continuity mistake: The whole time Siro is fighting the two guards his shirt becomes increasingly caked in oil except for a six-second segment in which it not only becomes sparklingly clean again but also alternates between being short-sleeved and long sleeved.
Stolen Lies - S1-E21
Continuity mistake: After Kung Lao and Siro have beaten the guy sent to recover the portal key, Siro pulls the man's mask off to check who he is. Cut to a close up and Siro pulls the mask off again.