In the calm lands you can go passed the monster arena into the next area, cross the first bridge and take the path down a hill to the Cavern of the Stolen Fayth.
Enter the cavern and you should find the Al Bhed Primer 25 and many chests hidden around. Keep exploring the caven until you come up against Yojimbo.
BOSS: Yojimbo
This should be an easy battle. Just attack with your strongest players and this should be no problem.
Once you defeat Yojimbo, keep on following the cavern until you find the chamber of the fayth. You can then pay Yojimbo to receive him as a summon.
BACK