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Val Ca'aul is one of the four lieutenants protecting Valus Ta'aurc during the Cerberus Vae III Strike in the Trenchworks. After the other three bodyguards are killed a Harvester drops off the Goliath Tank he pilots. He must be killed in order to advance to the next checkpoint.
Val Ca'aul is not actually encountered in-game since he is inside the Goliath Tank. He is known only through the objective descriptions.
List of appearances