Petri's Philter

Where to get the diagram

• Base Petri's Philter — sold by Otto Bamber at the Herbalist's Hut northeast of Oxenfurt, or Yolar at Gedyneith.
• Enhanced Petri's Philter — sold by the herbalist in a shop on Glory Lane, the herbalist in the Druids' Camp, or the herbalist at the Ruined Inn.
• Superior Petri's Philter — sold by Gremist at Gedyneith or Yolar at Gedyneith.

How it works

Petri's Philter raises Sign intensity for a short window, making every Sign hit harder and scaling any build pieces or mutations that key off that stat.

Base, Enhanced, and Superior

All tiers boost Sign intensity; higher tiers last longer and push the bonus further (15% → 20% → 25%).

The standout upgrade is Superior, which makes Signs always apply their special effects:

• Aard — 100% knockdown chance.
• Igni — 100% burn chance.
• Quen — guarantees enemy stagger when the shield bursts.
• Yrden — maximum slow percentage.
• Axii — triggers a full enemy stun.

Build synergies

Petri's Philter shines in Sign-focused setups that stack intensity: Griffin school gear, Forgotten Wolf gear, and Magic Sensibilities (Sign crit chance and crit damage scale with Sign intensity).

Use it alongside Tawny Owl or Ancient Leshen decoction to keep casting boosted Signs continuously — both restore Stamina so you can chain casts while the Philter is active.

Piercing Cold adds extra Aard damage that scales with your build. With Superior Petri's Philter, the guaranteed Aard knockdown sets up Piercing Cold's freeze for instant kills on foes that are knocked down and frozen at the same time — especially strong for AOE clears.

The superior version also complements non-dedicated Sign builds — it can be used before tough fights, since the guaranteed special effects above can turn Signs into reliable crowd-control or setup tools without investing heavily in the tree.