Struggling to figure out where to find POSEIDON in Horizon Forbidden West’s ‘The Sea of Sands’ quest? In this guide, we’ll break down exactly where you need to head to in the Las Vegas ruins and desert, as well as the brief steps you’ll need to take after that in order to capture it and return it to GAIA for Aloy’s plan to save the world once more.

Where to Find the Poseidon Subordinate Function in Horizon Forbidden West

Poseidon can be found in the large stretch of desert and ruins that once was Las Vegas. Specifically, you want to look for a building with various ‘tiers’ or floors to it, with water pouring out of its sides.

When you get close, Aloy will make a comment about “water pouring out of that building!” and it potentially being “POSEIDON’s doing.” You can find a screenshot of the building below, and we’ve also marked its exact location on the map above.

Getting Poseidon

Once you’ve found the building with all of the water spilling out, make your way inside by using your Pullcaster to reach the grapple point, and speak to the characters scrambling out of the water.

This is a continuation of this main story quest, and will see you helping them explore the underwater ruins. To do this, you’ll need to get your hands on the Diving Mask, which will enable you to breathe underwater.

Upon grabbing this, Aloy will then be able to explore the ruins underneath the building with the water pouring out of it. Prepare for an exciting battle and eventually you’ll get your hands on the Poseidon AI.

With it captured, you can now return to GAIA at your base (you can fast travel to the campfire just outside for convenience) to the east to continue on the main story quests of Horizon Forbidden West.

For more tips, tricks and guides, head over to our Horizon Forbidden West wiki, or see more of our coverage on the game below.

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