Isawa Ishi was a yojimbo of the Phoenix Clan and twin brother of Isawa Oriko, a powerful shugenja. For ten years the twins protected a village near the Phoenix Mountains from all manner of dangers. An immortal yobanjin sorcerer began to terrorize the villages near the mountains, an enemy they were not prepared to fight. The sorcerer confronted and cornered the twins in a blind canyon, who sacrificed themselves to bind the sorcerer on the earth, and all three were pulled into the heart of the mountain. The twins lived so long as the sorcerer did, and their life-force kept him chained within the earth. Shiro Sousei, which was built near the mountains, was named the Castle of the Twins after them.