Cauldrons are areas in Horizon Forbidden West that can be completed to unlock specific machine overrides and mounts. Overriding machines can force them to fight alongside Aloy instead of against her, and there are unique mounts that can be unlocked through completing Cauldrons. These dungeons can be found in various locations around the map, and they each have a recommended level.
Two of the Cauldrons need to be completed as part of the main story missions in Horizon Forbidden West. The other four available Cauldrons are optional, but completing them is worth the rewards they offer. Each Cauldron will have climbing challenges and a boss battle at the end that must be completed before overriding the core and unlocking the machine overrides. Some of the machine overrides will only partially unlock, so players will need to finish crafting them at the Base by collecting parts from the corresponding machine. There are a total of 19 machine overrides that require crafting to complete.
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By completing Cauldrons, players can unlock four mounts for Aloy to ride across the Forbidden West. From the start of Horizon Forbidden West, players will be able to use Chargers as mounts. The Sunwing, Bristleback, and Clawstrider can be unlocked as mounts for Aloy by completing Cauldrons, and none of them require any additional crafting. The mounts in Horizon Forbidden West can be unlocked in the IOTA, TAU, and GEMINI Cauldrons.
The Cauldron TAU, or Repair Bay TAU, is part of an early main story mission "The Dying Lands" in Horizon Forbidden West. The recommended level for this Cauldron is 15 making it the lowest level Cauldron in the game. Completing the Cauldron TAU will
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