Silksong Exhaust Organ walkthrough

After successfully making your way through the puzzling area that is The Mist in Hollow Knight: Silksong, you’ll find yourself in the Exhaust Organ section of Bilewater. Silksong’s Exhaust Organ is fortunately a small section of the map but there are a few things you need to do here to enter Act 2 of the game.

These include rescuing a lost Flea and beating an end of Act 1 boss that acts as an alternative to Blasted Steps’ The Last Judge. To make sure you don’t miss anything, here’s our Silksong Exhaust Organ walkthrough.

Silksong Exhaust Organ walkthrough

Assuming you have just left The Mist in Silksong, you’ll arrive in a long room. Head right to find a doorway you can enter.

Unlock the Exhaust Organ Bench

First things first, let’s get the Exhaust Organ Bench unlocked. Go right, past the Drapefly enemy, until you come to some platforms. Climb up these platforms and keep left to arrive at the Bench.

You’ll need to attack the Bench a few times to clear it of cobwebs, then you can rest at it.

Collect the Silkeater and unlock the shortcut to the Bench

Leave the Bench and this time, use the platforms in the prior room to go right.

Go past the first path leading upwards (it’s a dead end) and you’ll arrive at another Drapefly enemy as well as another upwards passageway that has steam periodically being blasted into it.

You want to use the Cling Grip Skill to climb up this passage while avoiding the steam, which will do two Masks of damage to you if you are caught in it. There are a few of these steam-filled passages we’re about to navigate but there are ledges along the way that you can seek safety on.

After this first steam-filled passage, you’ll need to climb a second one, before sliding down a third one. Be careful of spikes along the walls here, however.

After the three steam-filled passages, you’ll arrive at a crossroads. Drop to the bottom and head right, where there will be three cocoons. Attack and destroy them to receive a Silkeater.

Climb back up the passage you just jumped down and take the first left. You’ll come to a wooden barricade you can attack and destroy to clear the path.

This drops an elevator and allows you to drop down into the room containing the Bench we unlocked earlier. Rest if need be!

With the barricade removed, go upwards to the very top of this passage and head left. What might seem like a dead end is actually a hidden passage if you continue moving left, past the wall.

Be careful not to fall into the spikes below and head downwards (unlike me), then exit to your left. You’ll find yourself outside again.

Platform over to your left and upwards, avoiding the maggot-infested water, to find a lost Flea trapped in some tree branches. Attack the branches to free him.

Go back over to the door we just came out of – before freeing the Flea – and head back inside again.

Defeat Phantom and enter Act 2

Climb back up the following passage and head right, where there are more steam-filled passages to traverse. Head down the first passage, up a second passage, and finally, up a third passage while avoiding the steam and spikes along the walls.

At the top, head left until you find yourself locked in a room. You know what this means…

You will arrive at a boss fight against Phantom, a Hornet-like creature that is very difficult to tackle, but fortunately only does one Mask of damage with their attacks (most of the time). For help with taking this boss down, take a look at our Silksong Phantom boss guide.

After defeating Phantom, you’ll unlock the Cross Stitch Skill, which allows you to Bind Silk around Hornet’s needle to deflect enemy attacks and counterattack them.

Leave the Exhaust Organ and go to Grand Bellway

Following the fight, head left the Phantom's arena to reach and activate an elevator. Ride it to be taken further north. At the top, head left and attack the upcoming lever to open a door, allowing you to continue left. You’ll then need to ascend a passage covered in spikes using the Cling Grip Skill.

At the top, attack the lever to open a door below you and drop into it. Keep left, and you’ll arrive at the Grand Bellway Bench and Bellway Station, as well as your first Ventrica Station. It’s time to explore the Choral Chambers section of the Citadel next!

For more on Hollow Knight: Silksong, take a look at our list of all Tool locations, our list of all Lost Flea locations, and our Silksong walkthrough.