Dragon's Dogma 2 The Caged Magistrate quest guide

How do you free Dragon's Dogma 2's magistrate Waldhar? This surprisingly complex request from Captain Brant in Vernworth tasks you with liberating a potential ally in the fight against the queen regent. He's locked up deep within the castle's prison, and while getting inside shouldn't be a problem, getting him out is a challenge, as he's quite content where he is.
So begins a multi-part Dragon's Dogma 2 quest that requires you to complete another task first. So, if you wish to progress the RPG game's main campaign, we're here to tell you how to get inside the magistrate's cell and what you need to do to convince him to leave with you.
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