The X-Men #5

With Xavier's mental powers gone, the X-Men try to decide how they will function without his leadership. Trying to ferret out the X-Men, Magneto has the Toad enter an athletic event where he leaps to victory. With the crowd turning hostile due to the Toad's amazing abilities, the X-Men arrive on the scene to capture him. Magneto snags Angel and whisks him away to Asteroid M. In an attempt to trade the Toad for Angel, the X-Men arrive on Asteroid M where they battle the Brotherhood once again. On their safe return to Earth, Xavier reveals that his power loss was a ruse to test his students.