As part of the Halo Infinite campaign, you'll be tasked with capturing forward operating bases—FOBs, for short—to help rid Zeta Halo of the Banished. There are several Halo Infinite FOBs scattered through the open world and capturing them unlocks fast travel points, as well as marines to assist you and new vehicles. If you don't fancy sprinting your way across the map or hoping to stumble upon an abandoned Mongoose, here's how to capture them.
Halo Infinite FOBs: How to capture them
Depending on your chosen difficulty, capturing a FOB could potentially take a while, but there's usually a challenging enemy (glowing red) or two to defeat, some Brutes, and a bunch of Covenant enemies. In the centre, there'll be a terminal you can hack using the Weapon AI, but until you've cleared the area it'll be locked.
Once all the baddies are taken care of, you'll capture the base and the Weapon will provide you with a bit of lore. There's usually an audio log lying around as well as weapons and grenades you can pick up. You'll gain Valor when unlocking a FOB, which will unlock more weapons, marines, and vehicles. As you progress through the campaign and gain more Valor, vehicles like the Warthog and the Gungoose can be summoned.
Marines will spawn once the FOB is captured and will man weapons and jump in vehicles with you, too, which is handy if you're going to capture another base or tackle a story mission. You can also fast travel to these bases which makes traversing the map much faster. But to be honest, it's a lot more fun to grapple a Ghost from mid-air and boot out the pilot to commandeer it.