Take out Marauder Stronghold
The Masked Marauders
It is also related to a trophy titled The Masked Marauders, completing this mission will reward you with a silver trophy.
To do the mission, equip the Dune Hopper. Go to the Marauder stronghold, where you will fight some marauders. After defeating them, you will have to chase some Marauder vehicles. When you have defeated the last vehicle, an artifact for the astro viewer will be dropped. You will then receive a message from Seem.
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