1. Eliminate enemy heli before lift off
During the first firefight, you will need to make your way up a hill. At the top you will see a helicopter in the process of taking off. Destroy it before it lifts off to earn the challenge. To make things a little easier, you can use the secondary Titus weapon.
2. Destroy sentry turret (x2) while disabled
Hit a turret with an EMP grenade and whilst it is short-circuited destroy it. Do this twice to complete the challenge.
3. Eliminate enemy personnel (x4) with one round from Titus weapon
As written in the challenge description. There are a few places where enemies will bunch up. When you see this, pop a Titus shot into them. Kill four of them with one shot to finish the challenge off.
4. Eliminate enemy personnel (x10) with heli turret
Near the start of the mission, you will arrive at a helipad where you can interact with a vehicle turret. Kill 10 enemies with the turret to complete the challenge.
5. Eliminate enemy personnel (x30) while using optical camo
You will find the optical camo device soon after entering the underground lab. Simply activate this and then kill an enemy. Repeat 29 more times to unlock this challenge.
6. Destroy enemy ASDs (x2) by exploding nitrogen tanks
After getting off the elevator, your team will tell you to use the nitrogen tanks to eliminate enemies. destroy two of the enemy defense bots using the exploding tanks.
7. Eliminate enemy personnel (x10) with the Assault Shield
You can grab a shield after the first scene with the scientist. Once equipped, shield bash enemies to kill them. If you can kill 10 of them you will complete the challenge.
8. Protect ASD resource from destruction
When you reach the vault, you can access a container on the wall of the large room nearby to release a friendly defense bot. To complete this challenge, you must ensure that the bot survives the enemy assualt that happens after the scene with the scientist.
9. Collect intel (x3)
Complete the mission without dying.