How to Get the Secret Third Act in Hollow Knight: Silksong

Team Cherry's Hollow Knight: Silksong has a hidden third act that you might not have known about, which hides some of the game's most challenging enemies and contains even more for you to acquire. To get here, though, you'll need to complete a series of challenges, which will give you access to even more gameplay.

Before we move on, we'd like to issue an obvious spoiler warning: we'll be talking about finishing the game, including spoiling the final two bosses of the game, so we can get more into it. You've been warned!

In order to access Act 3 of the game, you'll need to go to The Slab, an obscure location that you may have already been subjected to if you got caught by the bug carrying a cage. To get here in the endgame during Act 2, you'll need the Key of Apostate, which is located in the Putrified Ducts.

Access to the Putrified Ducts is actually entirely optional and highly missable, with two possible entry points that require you to hit hidden walls. The first is going through Memorium and performing a series of elaborate jumps to break hidden walls where you might have saved Jubilana during Songclave Wishes.

At the end of the long road, you can walljump from the side, and then use your double jump to reach a second wall that you can cling to. Here, you'll find a breakable wall, with a bit more jumping to do that'll lead you straight to the Putrified Ducts.

Though this is the easier path, we recommend you tread the harder grounds, as you'll have to get through Bilewater regardless later on in the guide. In the Sinner's Road, at the very top-right of the map, past a lot of parkouring maladies, you'll find a large vertical section with a dead bug and an item on top of his corpse. Behind him is a breakable wall that leads straight to Bilewater.

Here, you'll begin a lengthy and arduous parkouring journey with a boss, Groal the Great, out the other side, alongside access to the Putrified Ducts; claim the soul the boss was protecting in the Bellhome — we'll need that later.

Once in the Putrified Ducts, the Key of Apostate is actually relatively close by, and this is what you'll be using to get to The Slab. To find it, you'll need to jump up and go through a sewer to the left, with the key being protected by a large, green monster that you'll have to sink a few blows into to get past.

After you've defeated him, you'll be able to continue forward, but when you reach the end of the pipe, make sure you jump and get to the other side, where you'll find a dead, caged bug. Breaking the cage will net you the Key of Apostate and access to The Slab.

To reach the new area and use the key, we'll be going back all the way to the Choral Chambers, where, somewhere along the middle, you can find an exit to the left that leads to a bridge. Past the bridge, you'll find The Slab — head down to where the Bell Beast station is, and you'll find the lock for the Key of Apostate, but don't forget to rest at the bench.

The Slab can be a twisting maze, but you'll need to find the Heretic and Indolent keys to be able to progress. As you get to the very heart of the world and complete the dungeon-like area, you'll find access to the First Sinner, locked behind a large gate (which was very reminiscent of setting the Hollow Knight free in the original entry).

The First Sinner isn't an overly difficult boss fight, and your respawn point is right outside the arena, so no walk-backs for this one are required. You'll just need some patience to get through the fight, but clear attack signs should allow you to make quick work of it (especially if you have everything upgraded to the maximum).

After you've defeated The First Sinner, head back to the First Shrine and talk to the Caretaker, who will tell you to gather important ingredients to defeat the boss atop the Citadel. To get these, you'll have to talk to his family:

• His brother, the Bell Hermit, is under Bellhart. Go right from the Bell Beast station, hit the bottom-right wall, and walk into it to find him.
• His sister, the Chapel Maid, whom you met at Bone Bottom during the beginning sequence of the game.
• His deceased brother, Groal the Great, whom you'll already have the soul of after defeating him in Bilewater.

Finally, after getting all the ingredients, you'll have to go back to Bone Bottom to the tutorial area, where there's a metal door that your Needolin can open. After enabling the Weavenest Atla and going to the bottom, jump to the right and climb up, which will lead you to a second-floor-like section.

One screen over, just before the water, jump up to the roof, and you'll find a section you can climb over. Inside this nook, you'll find the Snare Setter, and the final element that you'll need to unlock Act 3.

Go back to Caretaker, have him assemble the tool, and complete the game as usual. This time, when you're defeating Grand Mother Silk, use your Needolin to defeat her, and you'll use the snare.

The game will roll credits as usual, but to start Act 3, all you need to do is go back to the main menu screen and start your save file — it'll let you start where the game left off!