Intelligence (level 1)

• Base Sign Intensity +10%
• Unlocks level 2 Signs (Aard, Axii, Igni, Quen, Yrden)

Potion Brewing

• Enables brewing of potions
• Story ability

Rising Moon

• Sign Intensity +100%, only when the moon is rising (between 21:00 and midnight)
• Requires consumption of a mutagen (Golem's Pith potion) instead of a Talent

Intelligence (level 2)

• Base Sign Intensity +10%
• Unlocks level 3 Signs (Aard, Axii, Igni, Quen, Yrden)

Herbalism

• Enables identification and gathering of plant-based ingredients
• Geralt must read various books and/or be taught to identify and harvest each plant type

Monster Lore

• Gives bestiary (and related ingredients) entries for Barghest, Ghoul, Graveir, and Drowner immediately

(For any which Geralt has already learned, there is no advantage.)

Oil Preparation

• Enables creation of oils

Intelligence (level 3)

• Base Sign Intensity +20%
• Unlocks level 4 Signs (Aard, Axii, Igni, Quen, Yrden)

Knowledge of the Cleansing Ritual

• Enables performance of the Cleansing Ritual in Places of Power

Ingredient Extraction

• Improves yield of ingredients from both plants and corpses

(The description is wrong. It only works on monster extracts that cannot be obtained without the specific monsters bestiary entry. And it has no effect on plant extracts.)

Bomb Preparation

• Enables the preparation of bombs

Intelligence (level 4)

• Base Sign Intensity +20%
• Unlocks level 5 Signs (Aard, Axii, Igni, Quen, Yrden)

Focus

• Duration of Signs increased by 25%

Knowledge of the Life Ritual

• Enables performance of the Life Ritual in Places of Power

Magic Frenzy

• Sign Intensity +25%, only when Geralt has <25% Vitality

Intelligence (level 5)

• Base Sign Intensity +40%

Mental Endurance

• Signs cost 25% less Endurance

Intensity

• Sign Intensity +20%