Cairo is an Indigenous (possibly of the Apache tribe) travelling with Coburn because he once saved Cairo's life. He is usually quiet; preferring to use his knives in situations. He is seen to be very skilled, able to hurl them with deadly accuracy. He appears to be an expert tracker, being sent ahead to find out where Ivan Isaacs is. Later, he sees members of St. Vertinez kill a small child from an infected village, and attacks them. He kills most of them before his arm is cut off by a thrown spinning knife. He continues fighting and is then killed by Antione, a member of St. Vertinez with a hook for a hand. Afterwards, he is brutally dismembered. Seeing this, Coburn renounces the Vatican and says 'From now on, the cross will only be the sign of the enemy to me'.
During the battle of Windtale, an Indigenous chief, Cairo's brother, helps with a third unnamed Indigenous. During the battle Coburn uses one of Cairo's knives prior to his fight with Joshua remarking 'he saved my life more times than I can count'.