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Hollow Knight: Silksong

How to Get Plasmium Phial and Effects

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☆ Walkthrough in Progress: Bookmark for Updates!
★ Best Crest Builds | Best Tools
☆ Full Interactive Map of Pharloom!
★ Mask Shards | Spool Fragments | Abilities
☆ Boss Guides: The Unravelled | First Sinner
★ Wishes: Broodfeast | The Lost Fleas

Hollow Knight Silksong - How to get Plasmium Phial

Plasmium Phial is a Red tool that you can equip to your crest in Hollow Knight: Silksong. Check out how to get Plasmium Phial, its location, how to refill it, and its effects here!

List of Contents

How to Get Plasmium Phial

Complete the Alchemist's Assistant Wish

Map Location Overworld
Alchemist Assistant Map
Alchemist Assistant Main

Plasmium Phial can be obtained by completing the Alchemist’s Assistant side quest, which you can start by speaking to the Alchemist Assistant in the Wormways.

This quest requires you to locate three Plasmium Plants, all of which can be found without leaving the Wormways.

All Plasmium Locations

How to Refill Plasmium Phial

Refill from Alchemist Zylotol at the Wormways

Plasmium Phial Refill Location

Once you have used up all your Plasmium Phial charges, you can return at the Wormways and talk to Alchemist Zylotol to refill the tool for 20 Rosaries.

Rosary Farming Guide

How to Use Plasmium Phial

Equip to Gain Bonus Health

Plasmium Phial grants bonus health points when used. It has limited charges, and once depleted, you’ll need to refill it to keep gaining temporary health.

Be sure to equip this tool to increase your survivability against difficult enemies or bosses.

How to Heal

Equip the Architect Crest to Overdose

Hollow Knight Silksong - Architect Crest
Equipping the tool while the Architect Crest is active also allows you to overdose on Plasmium. When overdosed, you’ll gain health regeneration indefinitely.

Architect Crest Location and Best Build

Plasmium Phial Overview

Plasmium Phial Information

Hollow Knight: Silksong - Plasmium Phial Plasmium Phial
Slot Color Uses Refill Cost
Red 5 20
Effect
Spear-phial containing Plasmium. Injecting the liquid allows one to gain health beyond their natural limits.

Hollow Knight: Silksong Related Guides

Hollow Knight: Silksong - Tools Slim Banner

List of All Tools and Effects

All Tools Guides

Silksong Tools Guides
Best Tools for Each Type Best Silkshot to Get

All Red Tools

Hollow Knight: Silksong - Straight Pin Straight Pin Hollow Knight: Silksong - Threefold Pin Threefold Pin Hollow Knight: Silksong - Sting Shard Sting Shard
Hollow Knight: Silksong - Tacks Tacks Hollow Knight: Silksong - Longpin Longpin Hollow Knight: Silksong - Curveclaw Curveclaw
Hollow Knight: Silksong - Curvesickle Curvesickle Hollow Knight: Silksong - Throwing Ring Throwing Ring Hollow Knight: Silksong - Pimpillo Pimpillo
Hollow Knight: Silksong - Conchcutter Conchcutter Hollow Knight: Silksong - Silkshot (Forge Daughter) Silkshot (Forge Daughter) Hollow Knight: Silksong - Silkshot (Twelfth Architect) Silkshot (Twelfth Architect)
Hollow Knight: Silksong - Silkshot (Mount Fay) Silkshot (Mount Fay) Hollow Knight: Silksong - Delver Delver's Drill Hollow Knight: Silksong - Cogwork Wheel Cogwork Wheel
Hollow Knight: Silksong - Cogfly Cogfly Hollow Knight: Silksong - Rosary Cannon Rosary Cannon Hollow Knight: Silksong - Flintslate Flintslate
Hollow Knight: Silksong - Snare Setter Snare Setter Hollow Knight: Silksong - Flea Brew Flea Brew Hollow Knight: Silksong - Plasmium Phial Plasmium Phial
Hollow Knight: Silksong - Needle Phial Needle Phial Hollow Knight: Silksong - Voltvessels Voltvessels

Comment

5 Silksong Silksong 3 months

Can I still get this in act 3

4 Anonymous Anonymous 3 months

if you use an amount more than your max masks they will turn blue, giving you the ability to regenerate which can not be interrupted even if you get hit, so if you have 5 max health, you will have to use 6 plasmium vials to gain the affect, the affect is lost on death or resting at a bench.

See more comments (5 Comments)

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