Sofia wants to learn more about Arachne, the command center sending out signals and possibly causing her headaches. Go to the Uncanny Caverns and retrieve the Arachne holotape from a trunk inside the caverns. Return it to Sofia to complete the quest. Watch out for any hostile creatures in the caves, including some powerful mirelurk kings, while making it down to the steamer trunk the objective is in, located in the tunnel marked by the audio tour speaker and sign for point 8 on the tour outside of it.
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