Short answer
Third Eye Salt gives +2 to all five masteries — Building, Smithing, Farming, Book writing and Anatomy — for 7 minutes 30 seconds. Brew it from runes totalling 1 red and 5 blue after researching Transmutation I; Laboratory I is enough, because two-item mixes such as Alchemic Powder + Firefly or Alcohol + Firefly work. The Alchemist sells it from trader level 2.

The Astrologer's Tower
View full-size image ↗Official promotional screenshot · © Lazy Bear Games / tinyBuild · Official media kit · Material credits
The rune formula
Target: 1 red, 5 blue. Laboratory I or II can brew it.
Firefly is the common thread in easy mixes: Alchemic Powder + Firefly, Alcohol + Firefly, or Blueberry + Night flower + Firefly in a three-slot lab.
Each brew uses 1 Alchemy Flask.
What the buff does
Drinking it adds +2 to all five keeper masteries for 7 min 30 s.
Using another potion restarts the timer, so do not chain potions expecting the bonuses to stack.
Each use also adds +1 towards the Bottle Tester inspiration.
When it is worth a flask
Many recipes refuse to start below a mastery level. +2 on every tree can carry you over such a gate before you have earned the points.
Examples of high gates elsewhere on this wiki: Farming 14 for gold Wine at the Wine Barrel, and Smithing 15 for Master Armor and the Master Sword.
Drink it right before you queue the craft, because the timer is short.

The tech tree from the official media kit. Third Eye Salt adds to mastery, not to tech points; this is not a buff screen.
View full-size image ↗Official promotional screenshot · © Lazy Bear Games / tinyBuild · Official media kit · Material credits
Buying and selling
The Alchemist sells it from trader level 2 at a base 15 silver, and buys it back for about 11 silver 25 bronze.
Studying one costs 10 Science and pays 30 red, 30 green and 15 blue tech points.
Sources
- communitywikily.gg — Third Eye Salt
- communitywikily.gg — Third Eye Salt formula
- communitywikily.gg — Alchemy formulas
Related pages
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