12 Things Fox Want You To Forget Before X-Men: Days Of Future Past

2. That Xavier Forgot All About Magneto's Shiny Helmet

When Professor X introduces us to Cerebro in the first X-Men movie, he states not only that Magneto helped him build it, but that he also learned how to make a helmet specifically to block the machine's powers to keep his thoughts away from Xavier's prying mind. But that doesn't exactly fit in with what happens in X-Men: First Class where it is revealed that Magneto actually steals the helmet from Sebastian Shaw after killing him in vengeance for the death of his mother. In that movie, Shaw reveals that the helmet was given to him by the Russians as a means to block mental powers like Xavier's. So why did Xavier forget such a key detail as the source of the one thing that prevents him from stopping his greatest foe, when it also played a major part in their meeting in the first place?