The X-Men #7

The X-Men graduate from Xavier's school. The Professor says he is taking a leave of absence and puts Cyclops in charge. He shows him his new mutant-detecting machine, Cerebro. Magneto finds the Blob and invites him to join the Brotherhood. During a scuffle, Xavier's mental blocks dissolve and Blob remembers the secret of the X-Men. The Blob's name lights up on Cerebro and Scott calls the X-Men back to battle the evil mutants. During the battle, Magneto shoots missiles at the X-Men, even though the Blob is in the line of fire. The Blob, feeling betrayed, decides to return to carnival life.