Continuity mistake: When Leech picks up the gun to try to defend himself from the Reavers, he is in an underground area with brick walls. When Lady Deathstrike grabs him and asks why she should spare him, they are now standing in a tunnel with walls similar to a cavern. (00:02:50)
Continuity mistake: When Leech is telling Lady Deathstrike that Callisto forced him to steal from her, she has her hand wrapped around his neck. When the shot changes, her hand is now gripping him by the chin. (00:03:00)
Continuity mistake: The glove on Magneto's right hand disappears after Mr. Sinister blasts him in the back. (00:17:20)
Continuity mistake: When Slab tosses Cyclops, you can see Beast in the background, and he is crouching down. When the shot changes, he is standing upright. (00:05:09)
Continuity mistake: When the Nasty Boys and the Savage Land mutates confront the X-Men, you can see Slab is wearing the white belt that keeps his mutant powers intact. Later in the scene when he is attacking Cyclops, the belt is colored brown. (00:03:46 - 00:05:07)
Continuity mistake: When Mr. Sinister is criticizing Xavier for fawning over humankind, Morph is barehanded. When the shot changes, he is wearing gloves. (00:11:34)
Continuity mistake: When Gambit is watching Rogue being taken away, you can see the bars of their holding cell are only about a foot taller than Gambit. Later in the scene when Wolverine is attempting to free the X-Men from the cell, the bars now go all the way up to the ceiling. (00:14:13 - 00:14:48)
Continuity mistake: When Barbarus throws Wolverine onto the control panel, there are numerous buttons on it. Moments later when Vertigo is using her powers to disorient Wolverine, some of the buttons have disappeared. (00:14:56)
Continuity mistake: When Vertigo is telling Wolverine to become one of Mr. Sinister's slaves, the red diamond on Sinister's chest is the same blue color as his outfit. (00:15:32)
Continuity mistake: When Wolverine frees Morph and Xavier from their bounds, Morph and Xavier are suddenly closer to Magneto than previously shown. (00:15:32 - 00:15:59)
Continuity mistake: When the X-Men have their powers restored, Jean Grey is behind Cyclops on his right, near the front of the cell. When they begin running out of the cell, Jean is now several feet directly behind Cyclops, closer to the back of the cell. (00:16:18)
Continuity mistake: When Xavier helps Morph overcome Mr. Sinister's mind control, Wolverine, Storm, and Gambit are standing behind Morph, and Magneto is lying on the ground. When the shot changes, Storm, Gambit, and Magneto have disappeared. (00:18:35)
Continuity mistake: When Kazar and Shanna hug after he has freed her and the other captives, the lock on the cell door is missing. (00:15:30)
Continuity mistake: When Kazar and his people are storming the citadel, Morph and Xavier are spaced closer together than they were a couple of shots prior. (00:15:32)
Continuity mistake: When Shanna sees Kazar hiding around the corner, the guard has his eyes open. When the shot changes, his eyes are suddenly closed. (00:15:13)
Continuity mistake: After Ruckus prevents Kazar and his people from entering the citadel, Brainchild pulls a lever next to the door to seal them out. The lever in question wasn't there when Kazar and his people were first shown outside the door. (00:15:44)
Continuity mistake: When the lone sky-rider is flying towards Magneto, Magneto is grasping the cliff with his right arm. When the shot changes, Magneto is suddenly swinging from a tree branch growing out of the cliff in order to kick the rider off his pterodactyl. (00:03:22)
Continuity mistake: When Jean plays the message from Morph, the analog meters below the player are white. When the shot changes, they are brown. (00:05:09)
Other mistake: After Magneto says "Trust me, you'd rather not know," a hole appears in his pants around his right hamstring and then quickly disappears. (00:02:50)
Continuity mistake: When Morph, Jean, and Cyclops are all knocked unconscious by Ruckus' scream, Morph falls to his right, and Jean and Cyclops fall forward. A couple of shots later when their bodies are shown on the ground, Morph is suddenly between Jean and Cyclops, despite falling the opposite direction of them. (00:11:30)
