Horizon Forbidden West - All Cauldrons Guide

You can find Cauldron Locations in Horizon: FW, out of which 2 are story-driven and you can't really miss them. Overriding all Cauldron Cores unlocks the All Cores Overridden trophy, and unlocks the opportunity to override different machines in the world. None of them are missable, even after finishing the story.

Repair-Bay TAU

You will visit and override the first Cauldron automatically during main quest "The Dying Lands". You can't miss it. 

Overrides: Plowhorn, Bristleback

GEMINI

You will visit and override the first Cauldron automatically during main quest "Gemini". You can't miss it. 

Overrides: Sunwing

MU

Your first optional Cauldron (Level 18) is located southwest from Cinnabar Sands Tallneck.

Overrides: Burrower, Scrounger, Grazer, Scrapper, Fanghorn, Widemaw

IOTA

This Cauldron (Level 22) is located north of the The Shining Wastes Tallneck.

Overrides: Leaplasher, Glinthawk, Lancehorn, Longleg, Clawstrider, Skydrifter, Bellowback, Ravager, Snapmaw, Rollerback

CHI

This Cauldron (Level 30) is located south of the The Stand of the Sentinels Tallneck.

Overrides: Frostclaw, Redeye Watcher, Shell-Walker, Clamberjaw, Behemoth, Stalker, Shellsnapper, Spikesnout, Scorcher, Fireclaw

KAPPA

This Cauldron (Level 40) is located northwest of the The Stand of the Sentinels Tallneck.

Overrides: Rockbreaker, Tideripper, Tremortusk, Stormbird, Thunderjaw, Slitherfang, Dreadwing, Slaughterspine

Complete them all and All Cores Overridden trophy is yours.