Section 1 – Wharf District
Declassify Mission: Extra locust resistance in the area
You can activate the declassify mission in the starting area. Follow the stairs to join the bot. Grab the weapons and ammo then open the door to the marina. Take out the enemies in the area.
When you turn left from the door, you should find a COG tag skull on the wall ahead. Go near it then enter the alcove to the left to find a COG tag under the bulletin board.
There's also a ranged sentinel in the lower area but consider the risks before getting it. After clearing the first area, head to the second area where more enemies await. Be careful of the oneshot and mortar units.