First, you must have liberated Audvera Heights and Sable Lowlands before coming to Mount Ithaca. On the map, send a team up to liberate the town of Ketican. Do not liberate it until you see where Vad's team is located. Do not kill off Vad or Vad's team -- avoid him at all cost. After locating Vad's team, go ahead and liberate Ketican. Once that happens, the bridge east of town will blow up. Vad's team will not move unless you approach him. Liberate all the other towns and defeat Sir Rhade. Afterwards, you will see a group of Bolmaukans led by Vad who are unwilling to join with you, and have other plans of there own. Vad will insist that he joins you. Allow him to join. He will be equipped with a Touelno Claw, Thunder Chain and Hachigane.