Hollow Knight: Looking for a way to pass through Silksong’s corrupt duct? As mentioned at the end of the previous part of our Silkson walkthrough, corrupt ducts are just as unpleasant areas as you will encounter in Silkson. It’s like a smaller, more focused version of Bilewater, with even more nasty creatures. Thankfully, there are no giant bosses to fight in this area. It doesn’t take long to plunge into the surprisingly quiet pale lake on the other side.
in Part 31 of Silk Song WalkthroughI will guide you into a corrupt duct and show you exactly where you should go in stages to discover its secrets and the last one of all of the collectibles. Finally, we’ll show you how to turn this terrifying realm into a beacon of hope, and how to become one of Silkson’s most beloved resting places.
Do you need a walkthrough in another area of the game? Check out Hollow Knight: Silksong Walkthrough Hub!
Corrupt Duct Walkthrough Steps:
- Activates corrupt duct bellways.
- Get a corrupt duct map.
- Pick up a wreath of purity.
- Meet the fleas.
- Mining craft metal from pale lakes.
- Convinces the flea caravan to move.

1. Activate the corrupt Duct Bellway.
When you first enter the rotten duct, you begin a long, large corridor filled with water soaked with worms at the bottom. As you leave the door, directly below you are a new enemy relaxing on the wall, which is my least favorite enemy in the entire game: saliva.

The unstable movements in the air of these creatures, annoyingly high health, and tricky projectile attacks make them a real pain in the butt to deal with them. In general, I think it’s best to avoid fauna within the duct as much as possible.

With this in mind, go through the hallway and stay from the water below to the top level. You will encounter a giant charging creature you encounter at the top of Billwater, some platforms that Duct Soccer patrolled. Dodge them and continue until you reach the right side. Just below the exit is a shelf with a frayed rosary string, protected from above by the large tongue of Barnack. Collect it and then finish this awful hallway.


In the next room you can get down to the opposite entrance and exit marked with a Bellway sign. Inside, you can pay 80 rosary to unlock the final Bellway of the game. Additionally, on the right side you can pay 60 rosaries to unlock the bench.
2. Get a corrupt duct map.

Go back to the left, spit, then go above the bar and drop to ground level. There is a hole in the floor here, but don’t go through it yet. Instead, put the path on the left into a dark tunnel.


This place is full of bar bugs – don’t forget to attack repeatedly and get out of the clutch. Head to the left Deliberately Grab yourself and let Barnack’s tongue pull upwards. Once you’re close to the top, tear it freely and head to the right. Here you can return the way you come before picking up a map of corrupt ducts.

3. Pick up a wreath of purity.
Next up is a little trekking, but it will reward you with some very useful items for the area. Return to the previous room, lower the hole in the ground, then pass the shelf and lower the second hole to reach the bottom. First, take the left and cross some fragile walls to open a shortcut to the only previous area of the corrupt duct you explored. This is the area found at the top of Billewater where we found the keys for the Huntress and Apostates.
Now, backtrack, follow the path to the right and take you to another long, laborious hallway of scary creatures. Continue to the end, but once you reach the shelf leading to the exit, turn and jump into the wall above. From there you can reach the top shelf on the left.



From here, attack the Barnack hanging in front of you, temporarily withdraw it, then pass it and jump to the wall. At the top of this wall is a fragile section. Open it and continue along the path until you reach the hole in the ceiling and climb upwards.
Now you’ll find yourself in the middle of a small hallway. From here, head left and you will find some rosary caches. You can then jump over Worm-water and unlock the shortcut just below the Bellway.


Now backtrack and follow the path on the right, passing through the small corridor that passes through the spikes and bar. At the end of the pass there is an item on the ground. Pick it up and lease purity – these are very useful items for climates like these.

It is equipped with a purity lease, but is somewhat immune to the invasion of worms resulting from falling into the water, allowing you to swim in the water of decayed ducts (or bile water).
4. Meet the fleas.
Return to the left. Once you reach the Barnack, hanging on a bed of spikes, you will purposely catch yourself and pull it up to reach the top of the secret. Once you reach the top you will need to be free, put a claw line on the left and be caught again by another Barnack. Continue this way to pull the bar bug as high as possible.



Once you reach the top, head left and you’ll find a room with a new Grizzled NPC-Vog. She is a flea, but she is also a warrior and not a helpless lost flea to rescue, but the last of the fleas she finds. Tired of her dialogue will tell you that she is heading towards a flea caravan.
Once you’ve finished talking to Vog, head to the left of her shed and finally stand on the rocking ground, breaking it and falling once more into a rotten Ducts Bellway. A handy shortcut!
5. Mining the bow of a pale lake.


Rest on the bench again, then go left and head towards the unleashed shortcut under Bellway on the right. Go through it and drop it when you reach the hole in the ground you came up with. From here you can follow the steps to the far end of the hallway, avoiding most of the trouble below.
This time, you will pass through the exit on the right at the edge of the hallway. Jump over the wormwater below and grab your claws, head right and discover a much quieter area just on the edge of the pale lake east of the rotten duct.

At the edge of the lake is a musical instrument that looks strange. You can play Needlin before that and then light it up and then inspect some lore.
Beyond that, dive into the lake and swim to the very right side. At the end of the path, you can jump upwards into a small compartment using craft metal to extract from the wall.

6. Convince the flea caravan to move.
Now everything is explored in corrupt ducts. But there’s one more thing to do! Return to Bellway and move to the flea caravan. By this point, the flea caravan should be at the end of the blasted staircase (if not, head to that spot in Greymore and talk to Mooseka to move him forward).

As long as they discover a pale lake on the far east side of the decayed duct, they can speak to Fleamaster Mooshka and encourage them to move a caravan of fleas into a pale lake. Travel with them and after a short and adorable cutscene of the trip, you come back to the newly named Fleatopia, the final resting place for the flea caravan.
Talk to Mooshka again and as a reward for finding all the lost fleas in the game, he introduces the Flealia egg.

It ends our corrupt duct walkthrough and apart from rising the Citadel elevator into the cradle above, there is a precious little leftover. Just before that, some loose ends tie up, so join Hollow Knight Part 32: Silkson Walkthrough to learn what to do in preparation for the end credits of the game.
(TagStoTranslate) Hollow Knight: Silksong (T) Action Adventure (T) Indie (T) Nintendo Switch (T) PC (T) Platformer (T) Team Cherry