First, players need to play the story to Manhattan. After playing this map, the first main task can unlock the base and reward merchants in the base.

1. As shown below, the plot should be to play in Manhattan first. After playing this map, the first main task can unlock the base.

2. Don't go up the stairs and enter the door leading to the Science and Technology Branch.

Continue to take the stairs, you may meet soldiers.

Behind the stairs, next to the entrance to the underground world, there is a reward merchant.