Cauldron ZETA is the highest ranked Cauldron of them all, upon completion you’ll be able to override Thunderjaws, Behemoths and Stormbirds. When you get to it, you’ll find its entrance closed, but the outside of it patrolled by a number of Stalkers. On their own they are bad enough, but in groups they’re an utter nightmare, so be very careful here. Try to pull them one at a time which should allow you to keep control of the fight.
As always, best Stalker practice is to hit them with Tearblast first to peel off their guns and their stealth ability, then rope them down with a ropecaster, then punish. Repeat this until you’ve cleared them out. Once that’s done, there is a climbable column of rock near the entrance. Climb up it, then leap over to the cliff on the left, take out the Watcher, then proceed into the Cauldron.
Override the door to gain access, then just follow the path in front of you. Unlike the other Cauldrons, ZETA isn’t full of minor route puzzles, it’s just a straight shot to the heart as, waiting for you there, is a Thunderjaw.
Override the pylons containing it, then get ready for a nasty battle. Thunderjaws are incredibly dangerous in close quarters because it stops your ability to take out their main weapons from a comfortable range. It also allows them to do their incredibly damaging charge attack. Both of these things mean that you’ll want a full healing pouch, and a lot of traps. As soon as the fight starts, try to take out the disc launchers as they’ll be the bane of your life otherwise, then start flinging down blast wires and traps. In the small space, it doesn’t really matter where you put them as the Thunderjaw is very likely to walk into them at some point. If you can, get a hold of the disc launchers and pummel it with them, but your main focus in these tight quarters should be traps and wires.
When it’s down, override the Core and that’s you done.