Uncanny X-Men (1963) #543

No one can stop Colossus! The Juggernaut has become Kuurth, Breaker of Stone, one of the Worthy. Now more powerful than ever, one of the X-Men's greatest enemies rampages through San Francisco. To stop him, Colossus makes a deal with the demon lord Cytorrak-the being that imbued Juggernaut with his power. Can this deal be one Colossus can back out of at the fight's end? Prepare for the clash of two unstoppable forces! Part 4 (of 4).