Magneto has been wearing his distinctive helmet since X-Men #1. 1 / 8
However, early issues of X-Men also saw Magneto enter the astral plane to face Xavier. 2 / 8
And also project his mind all over the place, also seemingly astral projecting himself. 3 / 8
In X-Men vs. Avengers, Magneto had a plot to erase prejudice from the world. 4 / 8
The Avengers were trying to arrest him for crimes against the world. 5 / 8
He later noted that he had no telepathy and that the helmet would do it. 6 / 8
He later explained he had the telepathic circuitry in the helmet for years. 7 / 8
That circuitry is why Magneto is able to block telepathic attacks while wearing his helmet. 8 / 8