Fiend Saws: Phantom Blade Zero Weapon

Key points

Fiend Saws at a Glance

Secret-phase prize. To earn them, complete the Young Mistress tale, which means picking up the five ribbons of Mu Xiaokui prior to her showdown inside the Village of Lu.
Missable. If the ribbons are ignored, the third phase never shows up and that playthrough yields no saws.
Set up, then blow. Each strike feeds the Fiend-Aura Erosion meter. A full meter bursts and chews through the enemy's HP.
Fiend Form without blocks. Spend 1 Sha-Chi to drop into Fiend Form, where nothing you throw can be blocked and Guard-Broken foes take bigger hits.
Twin-blade burst. Wielded in both hands as a main weapon, it earns praise for heavy burst damage and for combining nicely with swift partners like White Serpent & Crimson Viper.
Upgrade component. Soul Tempering calls for the Heel Reinforcement Part. A sparring tale named Use It Against Them hands it out, and you fight that match with these saws.

Overview

Fiend Saws began as the blades Jade Dancer strapped to her legs and now belong to Soul.

Each is a curved blade with a serrated edge, and the pair plays around charging up and cashing in. Hits fill a meter on the target, you wait for it to burst, then push your advantage as the enemy's protection is stripped away. Instead of rushing a kill, the weapon stores up damage and returns all of it in one go.

Speed is their strength, with a style centred on rapid strikes and a straightforward way to deal damage that ignores guards via Fiend Form. You can also lose them for good, because the only source is an optional concealed stage of a story boss fight.

Figures

Stats at Level 1

Because Phantom Blade Zero has no published 0–100 bars for stats, this page gives the weapon's numbers as they stand at level 1.

Stat	Value
Weapon type	Dual-Wield
Wielder	Soul
Damage	302
Guard Break	120
How to obtain	Gather all 5 of Mu Xiaokui's Ribbons in the Village of Lu, then beat Jade Dancer during the hidden phase of that fight.
Added in	Base game

These numbers are taken from values the game itself lists for level 1; they were not confirmed through play.

How to Obtain

Before you start:

Gather five ribbons altogether, finishing the Young Mistress storyline
Get to Mu Xiaokui in the Village of Lu and beat her

Within the Village of Lu, wrap up the Young Mistress tale by tracking down all five ribbons of Mu Xiaokui. They are scattered about, including beyond the Gatekeeper Zhuo Bi, at the Temple of Blue Fireflies, around the Covered Bridge and by the Well of the Three Puppets.
Hold off on riding the elevator to the last boss until you hold all five.
Battle Mu Xiaokui, Young Mistress of the Order. Once the ribbons are in hand, a third phase is added, featuring her guardians Jade Dancer and Iron Fiend.
Beating Jade Dancer in this phase rewards you with Fiend Saws plus the Fist Fragment: Core, a key item.

Availability

Where	Status	Requirement	Note
Final boss of the Village of Lu	Missable	The Young Mistress tale must be finished prior to facing Mu Xiaokui	Skipping the tale means the third phase never starts and the saws are never given. Foes and bosses stay dead, so you cannot farm them again in the same playthrough.

How It Plays

Planting a charge and then setting it off is how the saws operate, and Fiend Form offers a second, more immediate source of damage.

Fiend-Aura Erosion

Every strike pushes up a Fiend-Aura Erosion meter on the target. Once full, the meter bursts by itself and bites into the target's HP, scorching the aura out of its body.

Fiend Form

Using the active art spends 1 Sha-Chi and shifts you into Fiend Form briefly. During it, all your attacks cannot be blocked, and enemies that are already Guard-Broken take additional damage.

Another hit while in Fiend Form unleashes a strong follow-up for no Sha-Chi, which then finishes the form.

Once it goes off

Endless Fiend Form, a Soul Tempering upgrade, gives the burst another purpose. After the Fiend-Aura Erosion of an enemy erupts, anything you aim at it cannot be blocked for a brief period.

Upgrade Paths and Versions

Level bonuses

The weapon can be raised from level 1 up to level 60.

Name	Unlock
Charged Onslaught	Level 5
Corrosion Burst (levels 1 to 3)	Levels 10, 20 and 30
Charged Frenzy	Level 15
Corrosive Severance	Level 25

Soul Tempering

Name	Effect	Cost	Unlock
Endless Fiend Form	When a target's Fiend-Aura Erosion bursts, none of your attacks on it can be blocked for a brief time.	1 Heel Reinforcement Part and 5,000 Remnant Dust	Use It Against Them, a tale, pays out the Heel Reinforcement Part

Pros, Cons and Ideal Situations

Strengths

Fiend-Aura Erosion converts constant striking into HP damage that lands after a delay.
In Fiend Form no blow can be blocked, and Guard-Broken targets take extra damage.
Endless Fiend Form sustains unblockable attacks once the meter has burst.
Following up out of Fiend Form requires no Sha-Chi.

Weaknesses

Fighting Mu Xiaokui without having completed the Young Mistress storyline costs you the weapon.

Best used for

Enemies that just had their guard broken, because Fiend Form deals them more damage.
Offensive team-ups, such as swapping to White Serpent & Crimson Viper after the guard shatters.

Weapon Comparison

Weapon	Build-up	Defence breaking	Source
Fiend Saws	Fiend-Aura Erosion gauge	Fiend Form unblockable attacks	Jade Dancer, Village of Lu
White Serpent & Crimson Viper	Nonstop strikes that drain Sha-Chi	Keeps pressure on	Main weapon
Bonesaw	Brutal shield-breaking	Crushing ending after guard falls	Main weapon

Background and Look

Jade Dancer once owned the blades and moved them with her legs before they reached Soul. According to their text, the fiend's aura absorbed into the steel remains undimmed, although a different wielder now holds them.

Quick answers

Frequently Asked Questions

How can I obtain Fiend Saws?

Finish the Young Mistress tale through locating all five ribbons of Mu Xiaokui, beat her, then take down Jade Dancer in the bonus phase.

Is it possible to miss Fiend Saws?

Yes. Should you face Mu Xiaokui while the Young Mistress tale is unfinished, no extra phase and no rewards from it will show.

What is the effect of Fiend Form?

For 1 Sha-Chi, it briefly stops any attack of yours from being blocked and raises damage dealt to Guard-Broken enemies.

Which source provides the Heel Reinforcement Part?

Use It Against Them rewards it. That sparring match pits you against Jade Dancer and Iron Fiend at the Crimson Forest Sha-Chi Tower, using Fiend Saws and Iron Gauntlets.

Fiend Saws.