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It is no secret that Hollow Knight: Silksong has some dark secrets lurking around every corner, but few are as creepy as a hidden boss locked inside an underground prison, right?
That is the case of the First Sinner, a challenging boss imprisoned within The Slab, which also brings back some old memories of the original Hollow Knight.
However, to gain access to its secret cell, you must follow a series of specific steps, including getting caught by scary flies scattered across Pharloom (or finding a special item) and cleaning up an entire region to gather prison keys.
It is quite a fun and weird (in a good way) journey that can feel a bit like a maze sometimes, but with the right path and a well-crafted plan, you can find and defeat the First Sinner in no time.
So, in this guide, we will show the easiest route to encounter this boss – which grants you one of the coolest Silk Skills by the way – as well as the best strategy to defeat it.
How To Find the First Sinner in Hollow Knight: Silksong
First, you must find The Slab, a region which is located (and can be accessed) on the left side of the Choral Chambers.
However, only finding it is not enough, since the whole place is like a giant prison, where you need the Key of Apostate to access its main corridors and cells. There are two different ways to get that special key: getting kidnapped by Wardenflies that carry a cage while freely exploring Pharloom (Act 1 or 2), or finding it on a dead body in the Putrefied Ducts (only Act 2).
We are aiming for the easiest and most secure route, so we are focusing on the second way of doing things – especially because you lost items and such on the first one.
Anyway, the Key of Apostate is located in a hole in the left wall (1) of the lower section of the Putrefied Ducts – the one that is connected and accessible from Bilewater. When you have the key in hand, quickly travel to The Slab and go up, following the first entrance to your right and using the item to open the first corridor of the prison (2).
From here, you need to explore every floor and cell to find two more keys: the Key of Indolent and the Key of Heretic (you can check their location on the map above). As soon as you get the latter, you are ready to find the First Sinner’s lair.
So, from the entrance of the prison, head down as soon as you can and search for the first entrance on your right, where you must use the Key of Heretic to open a cell (3). You will find a room with Rosaries and a chest – climb on the latter to be able to double jump (using the Faydown Cloak ability, which is unlocked at Mount Fay) and follow a hidden path on the ceiling.
Eventually, you will find yourself inside a chamber with a weird coffin (or something close to that) locked by four chains. Break them all, which will allow you to enter it and interact with the living “mask” inside it – triggering the boss fight.
Best Preparation For the First Sinner Boss Fight
In order to get a smoother victory, we will need a build that will make Hornet just as aggressive and agile as the boss is. So, you are going to want a Crest that allows you to deal short and quick strikes – and the Wanderer Crest is the perfect pick.
Also, you must have not only unlocked, but mastered three passive abilities for this fight: the Swift Step (the “dash”, which is unlocked in the Deep Docks), the Drifter’s Cloak (the glide, unlocked in Far Fields), and the Faydown Cloak (the double jump, unlocked in Mount Fay).
In terms of Tools, I highly recommend the striking combination of the Cogfly (can be crafted in a workbench in the High Halls) and the Pollip Pouch (obtained from the “Rite of the Pollip” quest), since you are going to trigger flying minions that can damage and poison your enemy, while you can focus on dodging.
And, if you need to give Hornet a little buff, the Fractured Mask (obtained from the Mottled Skarr merchant in the Hunter’s March), the Weighted Belt (obtained from the Mort merchant at Far Fields), and the Flea Brew (from the “The Lost Fleas” quest) can turn her into a more precise and agile warrior with an extra health point.
Oh, and I must warn you that, when you are defeated by the First Sinner, you will not lose your Rosaries. Instead of reappearing at a Bench, Hornet will be back at the coffin’s entrance like nothing ever happened – well, almost, since the Tools won’t refresh!
In the end, it means that it is actually more time-consuming than the standard death of reappearing at a Bench, since you will need to go back to the nearest Bench to refresh your Tools and come back to the coffin to try again.
How To Beat the First Sinner in Hollow Knight: Silksong
Phase One
Basically, the First Sinner has two different phases, and both present an interesting mix of long and short-range attacks, so I hope that your reflexes are sharpened up.
She has three different attacks in total – and I know that it feels like she has a lot more than that, but it is just a false impression due to the lack of standardized directions from her attacks.
The first attack is a kind of dash while on the ground, where she will try to cut Hornet with her nails. So double jump to avoid it, while also trying to counterattack a little bit.
The second one is a multiple slash in Hornet’s direction from the air: she will be gone for just a second and then suddenly appear in the middle air and come at you. Quickly dash (or double jump again) to avoid it. You can try to counterattack this one, but it is unlikely to work, since he will disappear again after delivering the second slash. So, it is better to be safe and dash to the center of the arena to wait for her next strike!
Finally, she will summon multiple nails in her third attack, which will try to slice you in half (vertically and horizontally). You must jump, glide, and position yourself quite well to avoid it – use your double jump, gliding, and dash in order to do that successfully.
Last but not least, you will notice that the First Sinner will try to “recharge” her Silk in some moments. That means that she is trying to heal herself (in a similar way to how Hornet heals in the game!), and you must immediately hit her to prevent her from healing.
So, knowing how to avoid all of her attacks (and also how to “block” her healing), the best strategy with this boss is to be aggressive from the very beginning. Use the fact that the arena is long to your advantage! For instance, after dashing from one of her attacks, she will reappear on the other side, so quickly run towards her and give a nice strike – you will deal extra damage by doing that.
Keep a safe, yet short distance from her and do not let her pace the rhythm of this fight, since you are the one who needs to do this. Maintain this mindset until she starts screaming, meaning that you have reached the second phase.
Phase Two
This is where things get even more complicated, since she will maintain all her moveset while adding a dangerous Silk Skill (yes, you did not misread that) and a whole new level of velocity.
You need to remain as aggressive as possible because we want this fight to be over as quickly as possible. However, you need to focus a bit on dodging at first, so finally activate your Cogfly to keep damaging and poisoning her. You can also try the Flea Brewer to give Hornet’s attack and agility a boost.
For her Silk Skill, she will summon a bunch of white circles in the whole arena that can burn you, dealing an awful lot of damage. To avoid it, simply stay in an area that has not been affected and wait for it to pass.
Take it easy at first until you understand her pacing, so that you can not only follow, but also dictate the rhythm of this dance again (always keep a Cogfly on the area, though). Once you do that, you will have your boss in the palm of your hand.
Rewards For Defeating the First Sinner
After defeating the First Sinner, you will get an immediate reward – and one of the best, coolest Silk Skills in the game, I must add. I literally feel like a pro player using it.
It is called the Rune Rage, a strong and dangerous technique, which is literally the circling, burning attack that she tried to kill Hornet with! Pretty neat, right?
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Author: 360 Technology Group
