Jack went to the coordinates given by Serpent Boss. It was the place where the Dogs of War members had discovered the enemy's command base. Jack found that he knew the place. He came to this place before with Grace. It was the large cave hall where Balgadur's main station was located. The hub where the carriages and the trains gathered.
He had used his corporeal state to scout the place and confirmed that Linda and the war table were there. From what he saw, he estimated around 30,000 soldiers were guarding the place. He might be able to force his way through if he went all out but he preferred to not take the risk. If Linda was allowed the time to flee and move the war table, then they would have to start looking for her again.
If he started acting, he had to get to Linda fast, so he stuck to the plan. He sent a message to John and Jeanny telling them that he was in position. Now, all they needed to do was wait for Serpent Boss' signal.
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