Look, the Cathedral of the Deep is a nightmare. It’s not even that the enemies are all "one-shot" gods like in the Nameless King fight, but the sheer endurance required to get through this place without losing your mind is a lot. You’ve got infinite-respawning zombies, bleed-inducing maggots, and those giant giants—literally—swiping at you while you're ankle-deep in muck. Honestly, if you aren't prepared for the sheer verticality of this map, you’re going to spend three hours just trying to find the second shortcut. This cathedral of the deep walkthrough is going to focus on the stuff people actually miss, like how to handle those pesky Grave Wardens and where to find Patches before he locks you in a tower.
Dark Souls 3 loves its loops. The Cathedral is basically one giant loop centered around a single bonfire. You’ll be coming back to the Cleansing Chapel over and over again. It’s your only home here.
Getting Through the Graveyard and Meeting the Infinite Dead
Once you leave the Sage’s bonfire and head up the hill, you hit the graveyard. This is where most players get frustrated. The zombies here don't stop. They just keep crawling out of the dirt. Don't try to kill them all; it's a waste of durability and Estus. Just run. You need to head up the path, veer slightly right, and look for the large gated entrance. If you linger, the "bleed" meter will build up because of the maggot-infested corpses. Pro-tip: Keep a torch in your off-hand. If maggots get on you, pulling out the torch instantly kills them and stops the bleed buildup. It’s a life-saver that most people forget about until they’re already dead.
Beyond the graveyard, you'll meet the first Grave Warden. These guys are fast. They dual-wield blades and can proc bleed in about two hits. My advice? Parry them if you’re confident, or use a high-stability shield. They have low poise, so if you're rocking a Greatsword, you can usually just bully them.
Opening the First Big Shortcut
After you get past the initial rooftop section—which is a gauntlet of thralls and evangelists—you’ll eventually reach a large set of blue double doors. This leads back to the Cleansing Chapel. Open this immediately. This is your lifeline. If you die after this point without opening the shortcut, you have to do that whole rooftop run again, and nobody wants that.
The thralls here are the real threat. They hide on ceilings and behind corners. They’re small, they’re fast, and they hit harder than they look. If you see an item sitting in the middle of a room with no enemies around, there are probably three thralls waiting to drop on your head. Always look up. It sounds simple, but in the Cathedral of the Deep, "up" is where 90% of the danger comes from.
✨ Don't miss: Marvel Rivals Sexiest Skins: Why NetEase is Winning the Aesthetic War
The Giants and the Muddy Floor
Inside the main cathedral chamber, you’ll see two Giants. They look intimidating, but they’re mostly just environmental hazards. They’ll try to smash you while you’re running through the sludge on the ground floor.
Here is what most people get wrong: they try to fight the Giants from the upper walkways. Don't do that. You can actually drop down into the muck and hack at their ankles. It’s disgusting, and you’ll move slowly, but the Giants are incredibly slow to react to anything happening at their feet. If you have a weapon with fire damage, use it. They hate it. Just watch out for the sludge-slugs that drop from the ceiling. They’re slow but can swarm you if you get greedy with your attacks on the Giant.
Finding Unbreakable Patches and Siegward’s Armor
This is the most convoluted questline in the game. To trigger the Patches encounter, you need to open the main front doors of the Cathedral (the ones near the second Giant). If you go up the lift and across the rafters before doing this, you might break the trigger.
- Find the well outside the Cleansing Chapel. Siegward is stuck in there.
- Go inside, open the big doors.
- Find "Siegward" (who is actually Patches in disguise) near the bridge.
- He’ll trick you. It’s classic Patches.
- Meet him again on the other side or back at Firelink Shrine to buy Siegward’s armor back.
Without this armor, Siegward’s quest ends. If you're a completionist, this part of the cathedral of the deep walkthrough is more important than the boss. You need that onion-shaped hero for later fights.
The Rafters: Where Gravity Is the Real Boss
If you want to join the Rosaria’s Fingers covenant, you have to go into the rafters. This is arguably the most stressful part of the entire level. You’re high up, the walkways are narrow, and there are Knights with Greatbows trying to knock you off.
🔗 Read more: Why EA Sports Cricket 07 is Still the King of the Pitch Two Decades Later
One trick is to use Alluring Skulls. Throw them off the edge, and sometimes the thralls or knights will just walk right off after them. If you’re a mage, Hidden Body is your best friend here. If you’re a melee build, bring a crossbow. Don't try to duel a Cathedral Knight on a six-inch wide beam. You will lose. Even if you win the trade, the recoil from your own swing might send you plummeting to your death.
Once you cross the rafters, you can drop down onto a balcony that leads to Rosaria’s Bedchamber. This is where you can re-spec your stats. You get five per "life cycle" (NG), so use them wisely. Just be careful: joining this covenant or giving Rosaria "Pale Tongues" will make Sirris of the Sunless Realms hate you. If you want her questline, stay away from Rosaria until you've finished Sirris’s story.
Deacons of the Deep: A Crowd Control Test
The boss of this area isn't a single monster. It's a mob. The Deacons of the Deep are technically one of the easier bosses in Dark Souls 3, but they can overwhelm you if you don't have a weapon with a wide swing arc.
- Phase One: Look for the deacon glowing with a red aura. That’s the "soul" of the boss. Kill that specific one. The aura will jump to another deacon. Repeat this until the main Archdeacon appears.
- Phase Two: Archdeacon McDonnell shows up with a bunch of fat guards. Now, you need to burn him down fast. If the fight goes on too long, they start casting a dark spell that covers the room in fog and kills you instantly.
- The Strategy: Use Alluring Skulls. The smaller deacons will chase the skull, leaving the boss wide open. If you have a weapon like the Hollowslayer Greatsword, you’ll do extra damage because these guys are considered "hollow."
Things You Probably Missed
There’s a hidden area behind an illusory wall near the entrance to the Deacons' boss room. It leads to the Deep Gem, which is great for certain dark-scaling builds. Also, don't forget to kill the mimics. There are two in the Cathedral. One drops the Deep Braille Divine Tome, which you should give to Irina of Carim—well, only if you want the "dark" ending for her. Honestly, giving her dark tomes is kinda mean, so maybe give it to Karla later instead.
Another thing: the Kirk, Knight of Thorns invasion. If you are embered and walking through the sludge area near the Giants, Longfinger Kirk will invade. Kill him for his barbed straight sword and armor. His armor is iconic—it deals damage just by rolling into enemies. It's not a lot of damage, but it's hilarious for finishing off players in PvP with 1 HP left.
💡 You might also like: Walkthrough Final Fantasy X-2: How to Actually Get That 100% Completion
Final Preparations for the Next Zone
Once the Deacons are dead, you get the Small Doll. This is a key item. Without it, you cannot enter Irithyll of the Boreal Valley later. You’ve basically finished the main path here, but before you leave, make sure you've:
- Checked the well for Siegward.
- Unlocked both main elevators in the Cleansing Chapel.
- Found the Estus Shard on the path near the graveyard (it’s on a monument surrounded by praying enemies).
- Grabbed the Paladin’s Ashes near the first bonfire.
The Cathedral of the Deep is a test of patience. It’s about managing your resources and not getting tilted by the constant bleed damage and thrall ambushes. Once you’ve mastered the shortcuts, the whole place shrinks significantly.
Next Steps:
Take the Small Doll and head back to the Road of Sacrifices. You’ll want to head toward Farron Keep next. Make sure you have some Purple Moss Clumps ready because the swamp is even worse than the Cathedral's sludge. If you haven't upgraded your weapon to +3 or +4 by now, go see Andre. The enemies in the next zone are much tankier, and you'll need the extra damage.
Check your inventory for the Dreamchaser's Ashes if you haven't found them yet—they're actually back in Farron Keep, but they're essential for buying Titanite Shards. If you've rescued Greirat, send him on his first pillage now; he’ll return after you kill the next boss.