Mission 21: The War Economy

- At the start of your first playthrough of this mission, you'll get a message that Mother Base is under attack. Immediately accept Mission 22 and return to mission 21 when you've completed this priority mission.

- Depending on what you wish to accomplish during your playthrough of this mission, it is either rather easy or quite complicated. The hardest objective by far is listening to all four conversations between the CFA official and the arms dealer. If you skip that, the other objectives are pretty much a breeze.

- You can bring Quiet along to mark targets for you.

- From the east LZ, make your way to the northwest corner of the airport and unlock the gate/door here. Immediately take out the Walker Gear here by using your tranquilizer gun (or if you're skilled enough, by grabbing/strangling the soldier from behind. There is a second Walker Gear on the other side of the hangar, but you can leave it alone.

- Mak[Subsistence] your way to the main building to the south, staying close or in shadows. Mostly crawl and move behind objects, especially as the gunship with the arms dealer arrives; lie completely still in the shadows as it appears. Mark the enemies on the main building and keep your eyes out for a soldier patrolling the containers to your left as you draw closer to the stairs. When the arms dealer moves out of the chopper, identify him, and when the coast is clear, take out the soldier on that level of the main building. Beware of the two snipers on the main building, though they shouldn't be able to spot you coming from this angle.

- If you just want to identify/neutralize/extract the CFA official and the arms deal, simply move up the stairs and tranquilize them both. The CFA official has full body armor, so aim for his head; otherwise he'll (try to) escape. Drag their bodies outside to extract them.

- Take down the gunship at an other playthrough; doing so right now is rather difficult unless you have access to homing missiles.

- If you want to listen to all conversations between the CFA official and the arms dealer, instead of going inside the building, overhear their first conversation by aiming your binoculars at their respective positions (be sure to have marked the arms dealer beforehand). Back away from the building and hide behind one of the containers; they'll move to the north hangar for their second conversation. After that they move to the south hangar for their third conversation. Lastly, their final conversation is back in the main building; you can extract them afterwards. The chopper will land at its original position too after their fourth conversation ends, so you can easily take it out with a rocket launcher.

- [Subsistence]-rank Tips: Simply ignore the (arrival of) the arms dealer completely and head for the CFA official; neutralize and extract him, then exfiltrate the area ASAP.