If you’re running low on fuel and metal, this trick lets you farm a good chunk fairly quickly.
If you’ve been busy sorting out your Mother Base in Metal Gear Solid 5: The Phantom Pain, you’ll know that not having enough fuel can severely limit your progress. While it’s generally better to focus on just what you need, having a surplus of fuel or metals can never hurt.
This is where this trick comes in. By replaying a certain mission in the game, you can keep extracting resources indefinitely.
Warning: there’s a spoiler of an early-game mission beyond this point. An Important side-op to be exact.
The trick is to replay episode 12, Hellbound (the one that sends you to extract Huey Emmerich). This side-op has containers of fuel, precious and minor metals. It takes place indoors however, so you will need to have the wormhole upgrade for your fulton unlocked. Skip the cutscene, turn back to where Sahelanthropus is kept, take out the guards and fulton away.
You can only unlock the wormhole upgrade fairly late in the game. After beating mission 31 and completing side-op 50, which asks you to capture a legendary jackal in Africa, you will be able to install the upgrade.
Now that you have your wormhole fulton, keep replaying Hellbound until you’re satisfied with the results. The materials will need some time to be process of course, depending on the strength of your Base Development platform, so just idle in menus afterwards.
You can also equip everything (you only need the pistol) when deploying, to save GMP and other materials.
Here’s a video of the trick, courtesy of Ekopingviini. Just make sure the game saves after each run.