Image 1 of 1 Marvel Comics Uncanny X-Men #125 CGC 9.8 (1979) 1st App Mutant X (Proteus) $399.00 Marvel Comics Uncanny X-Men #125 CGC 9.8 (1979) 1st Appearance of Mutant X (Proteus) Mastermind Appearance. Magneto cameo Add To Cart Added! Marvel Comics Uncanny X-Men #125 CGC 9.8 (1979) 1st Appearance of Mutant X (Proteus) Mastermind Appearance. Magneto cameo You Might Also Like Marvel Comics Uncanny X-Men #132 CGC 9.6 (1980) $175.00 Marvel Comics X-Men #5 CGC 9.8 (2024) ELIZABETH TORQUE 1:25 VARIANT ERROR $59.00 Zenescope Terror & Fury: Rise of the Night #3 CGC 9.4 (2025) $69.00 Marvel Comics Fantastic Four #142 CGC 9.8 (1974) 1st Darkoth the Death Demon! $450.00 Dragon's Lair #1, #2 & #3 CGC 9.6, 9.8, 9.8 CrossGen/MVCreations (2003) $399.00
