Plot hole: This episode showed that Beast was an original member of the X-Men and also depicted the original X-Men battling Magneto. However, when Magneto attempted to break Beast out of jail in the season 1 episode "Enter Magneto", Beast said to him "I don't believe we've met. Magneto I presume."
Add timeSerious B
Continuity mistake: When the group is standing together in a circle at the end, Xavier is sort of in the center of the circle and Rogue and Storm are several feet to his right. When the shot changes, Rogue and Storm are suddenly right next to Xavier.
Continuity mistake: When Xavier and the others are approaching Cyclops, Storm, Rogue and Wolverine, Magneto is shown wearing his helmet and Gambit is shown wearing his trenchcoat. When it changes to an overhead shot of the group, Magneto is no longer wearing his helmet and Gambit is no longer wearing his trenchcoat and his normally-black headgear is colored blue.
Other mistake: When Forge says "Now we need offensive power," he opens up a containment bubble with no one inside it. The bubbles are transparent, so he would have known whether or not someone was inside it and it would make no sense for him to open up an empty bubble since he was in need of reinforcements.