On my YouTube channel I've created gameplay walkthrough videos covering this game.
To get this you must complete the quest Percival Rackham's Trial. This is the main story mission following The Map Chamber mission's completion. Professor Fig will go to the tower (later identified as San Bakar's tower). The videos below contain the Percival Rackham's Trial mission. It begins at 39 minutes into the part 12 video and concludes at 36 minutes into the part 13 video. The quest involves clearing a goblin camp and a dungeon complete with a final boss fight.
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