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When the soldiers reach the cave where the party had taken refuge they come to realize that Colqhoun and Ives are one and the same. He had killed and eaten his five companions and is now set on trapping and killing them as well. Colqhoun succeeds in doing this one by one, including Colonel Hart, the fort's commanding officer.
Boyd manages to escape the massacre by jumping off a cliff but breaks his leg in the process. He hides in a pit next to the body of a fellow soldier. Eventually he eats some of the man's flesh to stay alive.
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Eventually Boyd gives in and eats a stew made out of the last officer killed and his wound heals.