Declassify Mission: Use Torque Bows and Breechshots only
Once the section starts, exit the tunnel and take the stairs to the left to find some bloodstains on the floor. The COG tag is located there.
Continue forth and you'll encounter the Declassify mission skull on the wall to the left. Continue until you reach the lift. Enemies will attack you with long-range weapons from across the ridge so find cover and take them out. The lift will go down, carrying a couple more locusts. Kill them and ride the lift up.
While riding the lift, more enemies will attack you from across the ridge again. The lift will provide no cover so you have to roll to evade and quickly take out the enemies. Once you've reached the top, you can continue to complete the section.