This walkthrough will help players navigate the optional Smouldering Lake area in Dark Souls 3. We will show you where you can obtain a pair of pyromancy tomes, earn a Black Knight Sword, and take down the shocking Carthus Sandworm on your way to the Old Demon King. Follow our steps to explore the Smouldering Lake’s fiery corridors and come away with valuable loot.
The Smouldering Lake is also tied to the storyline for Anri of Astora and Horace the Hushed. Players who hope to obtain the best and most complex ending should be concerned with the whereabouts of these NPCs. For more details on all possible endings, head over to our guide on how to obtain the best ending in Dark Souls 3.
The Smouldering Lake area is great for obtaining Titanite Shards. Most enemies in this location will drop Titanite Shards when killed, and the lake itself contains several Titanite items throughout. Consider returning to the lake to farm enemies in this location if you are in need of Titanite Shards to upgrade your weapons and shield.
Comb Through the Catacombs
To reach the Smouldering Lake, you must first make your way through the Catacombs of Carthus. After running across the footbridge leading to High Lord Wolnir, cut the ropes on the bridge to cause it to drop. The bridge will then act as a ladder. Climb down the new bridge ladder to reach a chamber below containing a Fire Demon. Follow our Catacombs of Carthus Walkthrough for details on how to defeat this fiery creature.
Proceed through the doorway past the fire demon and reanimating skeletons. Enter the hallway and turn right to reach the Abandoned Tomb Bonfire. Ahead of the bonfire is a cave passage that leads to the ground level of the Smouldering Lake.
The lake is a large open area that consists of Crabs, a large Sandworm, and a lethal ballista that fires in threes every few seconds. When coming from the Abandoned Tomb bonfire, the ballista is up high to the right. When you step out into the water, the ballista will begin firing at you. Use the nearby trees and wall ruins as cover when maneuvering across the lake. To the far right are a group of fiery Crabs that can overwhelm you easily. It’s better to disarm the ballista first before trying to collect the items throughout the lake.
As you run toward the doorway to the far left, a large Carthus Sandworm will emerge from the ground. This creature begins to shoot lightening at the ground when you come close. Don’t worry about fighting the Sandworm just yet. We are first going to show you how to disarm the ballista before dealing with the Sandworm and the other items in the water.
Old King’s Antechamber Bonfire
There are two routes you can take in order to reach the ballista at the top. Many players will begin by heading up the hill just beyond the Sandworm to the right. This path leads to the Demon Ruins Bonfire in a small room at the top. While this is a fine route to take, we are going to start by showing you a quick shortcut to the Old King’s Antechamber Bonfire first. This bonfire will place you much closer to valuable items, such as the Izalith Pyromancy Tome and Black Knight Sword. If you wish to take the route from the Demon Ruins bonfire instead, go ahead and skip down to the "Demon Ruins" section below.
Starting at the Abandoned Tomb bonfire side of the lake, run across the water toward the center, using the trees as cover from the ballista shots. Look for a patch of bricks in the center of the lake near a pair of rock stacks with candles on top. Stand near the edge of this brick patch so that the ballista shoots its center. The ballista will blast a hole into the ground, allowing you to drop down beneath the lake.
When you drop into the hole, you’ll end up in a hallway that goes in two directions. Around the left corner is a Crystal Lizard that will drop a Chaos Gem when killed. Around the right corner is a Demon Cleric. This creature attacks you with fireballs and streams of fire. It can also conjure a floating fireball that will target you when near. Defeat the Demon Cleric and continue through the hallway.
At the hallway intersection, to the left is a room containing the Old King’s Antechamber Bonfire, and to the right is a room with three Smoldering Ghrus, two of which are flanking the doorway. Lure each one into the hall to fight them individually, and watch out for their poison.
Clear out the enemies, then collect the Izalith Pyromancy Tome from the middle shrine. Return to light the bonfire, but don’t rest unless you need to. The Demon Cleric will return to patrol just outside the bonfire door, and can notice you near the bonfire very easily.
Ahead of the bonfire is a set of stairs going down. Before heading downstairs, go over to the corner on the right and attack the illusory wall to reveal a hidden passage. Straight ahead in this passage, you can observe a lower area that contains multiple Demon Clerics.
To the left in the hidden passage is a long hallway, lined with Writhing Rotten Flesh blobs along the ceiling. Unlike the flesh blobs in the Catacombs, these ones are smoldering and are not vulnerable to fire. The blobs will drop down as you pass beneath them, so be careful of this as you run through.
At the end of the hall is an Estus Shard just before a large hole in the floor. Across you’ll see a Stone Demon guarding another item that we will help you retrieve later. For now, you will have to run back through the hall the way you came. Lure the rotten flesh blobs down and destroy them ahead of time, otherwise you’ll have to deal with them on the way back.
Return to the bonfire, and this time go down the staircase. Ahead is a room with several more Smoldering Ghru. Head down the first hallway on the right, and turn right again to collect an Ember off a corpse. The hallway connects back to the other side of the room with the Ghrus. Go toward the room from either direction, and clear out the Ghru enemies.
As you enter the doorway to the next room, watch out for some crawling Ghru waiting to ambush you. These enemies are fast, and can jump on you quickly. There is also a Stone Demon around the right corner that will attack you with a stream of fire. Dispatch the enemies quickly, then enter the hallway in the corner.
Continue to the end of the hall. Turn left and attack another illusory wall to reveal a hidden chamber. There is a Black Knight fighting a Ghru as you enter the room. Take down the knight, and try not to back yourself into a corner while fighting. When the knight is defeated, be sure to collect the Black Knight Sword on the right side of the room.
From here, you can now enter the lower room with the Demon Clerics. At the far end of the area is an Undead Bone Shard guarded by a Writhing Rotten Flesh blob that drops onto your head as soon as you approach to take the item. Eliminate the Clerics and grab the shard if you wish, but the true path you should focus on is down the hall to the left.
There are two staircases on the left wall in this lower area. Both of these staircases lead up to a floor containing multiple Ghru enemies, as well as another staircase that leads to the Demon Ruins Bonfire. We will cover the items on this upper floor in our Demon Ruins subsection below, which we will explain as if coming from the outer lake. Continue to “The Demon Ruins” section now if you wish to know what items are on the upper floor. Otherwise, skip down to the “Into Quelana’s Passage” section of this article to collect another tome and proceed toward the ballista.
The Demon Ruins
Starting from the Abandoned Tomb bonfire, look out across the lake for a brick wall on the opposite side, slightly to the right of the Sandworm. There is a Ring behind this wall. Have the ballista shoot and break the wall for you to collect the Speckled Stoneplate Ring, then run past the Sandworm to the right.
Just beyond the Sandworm, you’ll see a door at the top of a staircase, as well as an uphill path to the right. The door leads to the Old Demon King, which we will deal with later. If you are ready to fight this boss now, feel free to skip down to our boss battle section below. For now, head up the path to the right and collect a Large Titanite Shard off the corpse on the ledge. Go down the stairs to reach a room that contains the Demon Ruins Bonfire.
Proceed through the hallway and down the stairs to reach a new floor of enemies. Before entering this area, take note of the nearby enemies. There is a Demon Cleric to the left who will lob fireballs at you. To the right is a Smoldering Ghru, who can inflict poison damage like the ones you encountered in Farron Keep. Lure each one to fight you individually in the hallway to prevent having to deal with both at once.
To the left near where the Demon Cleric stood, there is a corpse over the railing that holds an Ember. The stairwell to the right leads down to a lower area containing multiple Demon Clerics. Don’t go down the stairs just yet. Instead, continue along this upper floor to the far right, where you will encounter another group of Smoldering Ghru. Carefully lure each enemy toward you to defeat them one at a time. Watch out for the poison smoke cloud emitted by one of the Ghru.
Once you have cleared out the enemy Ghru, continue to follow the railing around the left corner. You’ll notice another stairwell, but ignore it for now. Proceed toward the archway at the far side. As you enter the room, watch out for an enemy Ghru who will run to ambush you from the left. Take him out, along with his friend sitting straight ahead.
In the archway on the left corner, you’ll see another glowing item corpse guarded by a Writhing Rotten Flesh blob on the ceiling. Approach the item to force the blob to drop so that you can destroy it. Directly to the right of the item corpse is a Stone Demon that will attack you with a fire stream. Quickly destroy the enemy, then pick up the Ember from the corpse. Across from the corpse is a hallway with a hole in the floor. If you followed along with our steps in the Old King’s Antechamber section, then you will have already collected the Estus Shard on the corpse ahead.
Return to the stairwell that leads to the lower area patrolled by Demon Clerics. On the far right side of this lower area is an Undead Bone Shard protected by another Writhing Rotten Flesh. Defeat the enemies and collect the shard if you wish.
There is a path on this lower level that leads to the illusory wall containing a Black Knight, as well as the items covered earlier in the "Old King’s Antechamber Bonfire" section. On the right corner is a hallway where you will see a single hound-rat. Follow along with the "Into Quelana’s Passage" section below to see where this hallway leads.
Into Quelana’s Passage
From the bottom level where the pair of Demon Clerics patrol, enter the hallway that contains a single rat. Straight ahead is a dead end, as it only leads to a hole in the floor to a pit of lava. Instead, turn right into a room that contains several more rats. Exterminate the rats, then attack the vine-covered wall in the right corner to reveal a hidden passage.
Turn left, and pillage the remains to obtain the Quelana Pyromancy Tome. Further to the left is a staircase leading down to a lava pit. In the lava are two collectibles: Toxic Mist and a White Hair Talisman. If you have high fire resistance and are prepared to down a few Estus Flasks along the way, you can brave the lava to reach these collectibles. Otherwise, disregard the lava pit and return to the previously rat-filled room.
Proceed through the archway into the hall ahead. You will now be on the other side of the hole in the floor from earlier. Continue down the stairs to the right. At the far end of the corridor to the right is a large hound-rat. Eliminate the foe, along with another group of rats sitting behind it. Afterward, strike the wall to the left of where the large hound-rat stood to discover an illusory wall hiding a chest. Don’t worry, it’s not a Mimic.
Open the chest to obtain a Large Titanite Shard. The wall behind the chest is another illusion. Strike the back wall to reveal a step leading down to a room full of Basilisks. You can also reach this room by going down the left staircase just before you fought the large hound-rat. However, if you want an Izalith Staff, you will have to drop down to the step below.
Defeat the Basilisks, then collect a Titanite Scale off the corpse on the right. There is a large staircase ahead that leads to a tough Black Knight. The passage on the left leads down to the lava pit. Beware of the left passage, however, as Knight Slayer Tsorig will come running up the corridor to attack you.
Tsorig wields a hefty Ultra Greatsword, and he is capable of draining your stamina and health with each successful hit. Lure him back toward the large stairs to have more room to fight. If you’re sneaky, you can lure Tsorig toward the knight at the top of the stairs, and they will duke it out. Tsorig will likely still remain standing, but this method leaves you with one less foe to face on your own.
Defeating Knight Slayer Tsorig rewards you with the Knight Slayer’s Ring, Fume Ultra Greatsword, and Black Iron Greatshield for your efforts. If either of you kill one another, you will receive the My Thanks gesture as well. In the lava where Tsorig once patrolled, you can collect a Sacred Flame if you are willing to brave the pit.
After dealing with Tsorig, continue up the large staircase toward the solitary Black Knight. Try to anticipate his movements, and roll behind him to strike him in the back. Lure the knight toward the staircase so that you don’t have to fight on the narrow bridge. Defeat the knight, then collect the Soul of a Crestfallen Knight from the corpse on the right ledge.
Climb up the long ladder at the back of the alcove ahead. The lower right ledge contains a corpse holding a Dragonrider Bow. Drop down to collect the item, then go down to a spot between ladders and climb back to the main path.
Disarm the Ballista
The ballista not far from here. However, there are still a few enemies to eliminate along the way. Head down the path slightly to the left, and you will find another item corpse that holds a pair of Homeward Bones. This lower path is protected from ballista fire, allowing you to focus on taking down enemies.
At the base of the path are several Wheeled Skeletons to the right, and some regular Skeleton enemies to the left. Lure the wheeled enemies out to eliminate them first before turning your attention to the other skeleton foes. Further up the path is a pair of Skeleton Swordsmen, one of whom shoots poisonous darts. Dodge their swift attacks and take down both enemies to clear the path.
Ahead you will see the ballista. Don’t worry, the giants aren’t alive. Walk beneath the underside of the ballista and push the lever to disarm it. The ballista will stop shooting, allowing you to freely collect the items strewn across the lakebed below. To get back down, you can either drop down onto the large stone steps over the cliff edge near the ballista, or simply use a Homeward Bone to return to a bonfire.
Defeat the Carthus Sandworm
Now that the ballista is disabled, head back down to the lake level to face the mighty Carthus Sandworm. It’s easier to reach the Sandworm from the Demon Ruins Bonfire, but if you don’t have that one lit, then start from the Abandoned Tomb Bonfire instead. You can fire arrows from a distance to defeat the Sandworm, but we will show you a more efficient method.
The Sandworm will emerge from the ground and coil around itself momentarily before diving back underground. The Sandworm will repeatedly emerge to shoot the floor in the center of the lake. There is a small section of land directly behind the Sandworm where you will be safe from its attacks.
Stand in this safe spot and wait for the Sandworm to raise its head up from underground to blast the lakebed with lightning. Run up to the Sandworm while in this safe spot, and start attacking it from behind as much as possible. When it is about to move again, back away to avoid getting hurt. Attacking the Sandworm while it’s moving will result in getting knocked back and incurring a lot of damage.
If you did not disarm the ballista, you can actually stand in this same patch of land and use the ballista shots to kill the Sandworm. However, you will likely get struck by the ballista as well, so just be prepared to drink some Estus Flasks while the ballista does all the work.
As long as you remain on this safe patch of land and attack when you have the chance, you should be able to take down the Sandworm without taking much damage. Defeating the Carthus Sandworm rewards you with a Lightning Stake spell and an Undead Bone Shard. Pillage the corpses at the base of where the Sandworm once stood to obtain a Large Titanite Shard and a Shield of Want.
Find Horace the Hushed
Head towards the Giant Crabs on the far side of the lake, opposite the Sandworm. Several Crabs patrol the area in a large group, and they can be quite overwhelming if you attract more than one. Defeat the Crabs if you wish. You can find Large Titanite Shards on the corpses near the Crabs, as well as a Chaos Gem on the corpse to the left.
From the Sandworm side, walk along the right side of the lake, keeping close to the right wall. About halfway to the Crabs, look for a narrow opening in the rocks. Inside this passage, you’ll find two Crystal Lizards that drop Twinkling Titanite and a Titanite Chunk when killed.
Proceed through the passage to find Horace the Hushed on the far side of the alcove. Horace has unfortunately become hostile, and will attack you once you approach. His halberd reaches far, so be prepared to dodge or block when he lunges toward you. Back up and use ranged attacks if needed. Defeat Horace to receive the Llewellyn Shield, then pillage the nearby corpses to obtain Yellow Bug Pellets and some Large Titanite Shards.
Now that you have gathered everything there is to find throughout the Smouldering Lake, it’s time to take on the Old Demon King. Head to the doorway at the top of the stairs behind the Sandworm to begin the battle with this fiery foe.
Boss Battle: Defeat the Old Demon King
As you approach the remains in the center of the boss chamber, the Old Demon King springs to life and is ready to burn you to a crisp. As with most boss encounters, we recommend using an Ember and summoning an ally for this tough encounter.
On the outer stairs leading to the boss chamber, you can summon the Great Swamp Cuculus NPC mage, as well as other online companions that tend to place summon signs here. If you defeated Knight Slayer Tsorig either in the Catacombs or near the lava pit, he will become available to summon from inside the boss arena. Look for his summon sign near the doorway before waking the fiery beast.
The Old Demon King has a variety of different attacks, with surprisingly far reach. Along with his powerful mace swings and slams, the demon can conjure fiery magic attacks that have a large area of effect. Use the two corpse mounds in the center of the arena to shield yourself from some of the attacks.
Bring the Demon King toward the corpse mounds, and wait for him to perform an attack. He will stand still long enough for you to come up from behind and inflict some damage, as long as he was not performing a ranged attack. Don’t linger near the beast for too long, as he can quickly shift between long and short ranged attacks.
The Old Demon King will spew a stream of fire from his mouth, and can detonate a giant fireball in his palm when you get too close. Unfortunately, you will need to get close to attack him if you don’t have a ranged attack, so just be prepared to dodge away when you see him raise his hand. Most of his close-range attacks occur in the front, so try to stay behind him near his tail to avoid these damaging attacks.
When his health is reduced to nearly half, the Old Demon King will begin using a more dangerous spell that launches tracking fireballs in your direction. Dodge away to avoid getting hit by the fireballs. The Old Demon King leaves himself vulnerable while conjuring this attack, so move in quickly to get in a few more hits before backing away to safety.
Once the Old Demon King is defeated, you will obtain the Soul of the Old Demon King, which can be taken back to Ludleth for transposition. Ignite the Old Demon King Bonfire near the center mound, and pat yourself on the back for a job well done.
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