The catalyst

Once a member of a renowned party. Until one fateful day when they went into a cave full of asphyxiating quartz. As they traveled through, they unknowingly inhaled quartz dust. When they tried to leave the cave collapsed in sealing the party in. After spending a day in the cave they woke to a sharp pain in their breath. And as they saw the small crystals forming on their skin, they realized they’ve been infected. As each member succumbed to the blight one by one. His mind, overwhelmed with looming dread had gone mad. As the last one left he waited, and waited but nothing. It had seemed he had conquered the infection but with his growing hunger gnawing at his mind, he ate his left arm. From where his arm was sprouted crystals forming a new larger arm but with the bodies of his fallen team lying around. He had no other choice but to eat them. Now he waits, sealed away in a mountain where nobody has ever found him.