Destroy metal-pedes in nest is a mission in Jak 3. Sig spotted an eco crystal within the Metal Head cave, but gigantic Metal Heads had been reported en masse inside. Jak took the chance to go and take the crystal by hunting down the metal-pedes inside.
The PlayStation 3 and Vita versions of this mission are related to a trophy named "Empty Nesters", completing this mission will reward you with a bronze trophy.
There are five of these spread throughout the cave, though they only appear one after the other. There are also many pod spiders so you cannot at any time stay still, or your vehicle will be eaten away. The metal-pedes are very strong and have a pretty accurate and fast-firing shooter on their foreheads, so concentrate on avoiding their shots wile simultaneously driving around them. If done well enough the turret should automatically whittle down their bit by bit.
They pop out of the ground here and there and will pretty randomly show up at various places in the caverns. Try to avoid bumping into them, it is futile as they just bump you back without any health lost. Concentrate on conserving your health for the majority of this mission and you will be able to kill them all.