This Exotic catalyst (and all that surrounds it) is worth the trouble.
Destiny 2's Sundered Doctrine dungeon launched the Finality's Auger Exotic, and it only took three weeks for players to find this Exotic catalyst. As expected, it's tied to the dungeon itself, and its acquisition is closer to Ice Breaker than to the catalysts of other dungeon Exotics.
Getting the Finality's Auger catalyst takes a bit of work. You must complete the Drowning Labyrinth quest before you can grab it, which requires a few clears of the dungeon itself. In that sense, Sundered Doctrine takes after Vesper's Host and Warlord's Ruin since both Exotic catalysts require you to clear the dungeon's quest. This means you don't have to do the dungeon on Master or be at the mercy of RNG to score the catalyst, which is helpful.
If you've completed the Sundered Doctrine quest, the catalyst is a freebie at the end of the dungeon quest, provided you already have Finality's Auger. And if you don't, you can likely grab it off the chest at the end of the dungeon once you get the Exotic. We've listed how to find the catalyst below.
The Finality's Auger catalyst drops from the secret vault inside the Sundered Doctrine dungeon. This is through the door behind Kerrev, the Erased, the dungeon's final boss. The door only opens after completing the Drowning Labyrinth quest, and the catalyst is inside a chest near the huge artifact in the room. It's unclear if you need quest progress to open the chest or if you can get it after being taxied by a player who meets the conditions, though.
Even if you don't have the Finality's Auger Exotic, finishing the Drowning Labyrinth quest lets you focus your drops in the Sundered Doctrine dungeon once per character per week, and you need the quest to find all nine collectibles. Doing so unlocks a triumph that boosts the drop rate of Finality's Auger, making it slightly easier to snatch this Exotic.
Finality's Auger gets Bait and Switch once you complete its catalyst objective, which isn't a bad deal at all. Bait and Switch improves your damage after hitting any target with your three weapons, and it's become a go-to perk for drops that go on your heavy slot. This legendary perk launched alongside the Vow of the Disciple weapons in The Witch Queen, and it's a fitting addition to the Exotic from a dungeon inside Rhulk's pyramid.
The main functionality of Finality's Auger is its Ruinscribe Turret, a Pyramid artifact that fires lasers at nearby enemies. You can control its aim, so you can have the turret as a backup damage source, like a super beefed-up Arc Soul. We don't know if the turret inherits the boost from Bait and Switch, but the catalyst makes this weapon much better regardless if you're using it to damage bosses.
Aim to unlock the Finality's Auger catalyst even if you don't have the Exotic. If this linear fusion rifle is already in your collection, Bait and Switch is one of the most prevalent damage perks, so it's essentially a free damage boost. The Exotic becomes far stronger if the turret inherits the buff, though we haven't tested that yet.
If you don't have Finality's Auger, though, the prerequisite Drowning Labyrinth quest gives you plenty of rewards, including the ability to focus dungeon loot and a triumph that boosts the drop rate for the Sundered Doctrine Exotic. The latter might save you from RNG, and the former helps you stock up on the handful of brilliant weapons in the dungeon. And if you're fashion-minded, the Sundered Doctrine class item also drops at the end of the quest.