Alchemy Skills/Abilities are one of the 4 Skill Trees in the Witcher 3: Wild Hunt. These abilities improve Potions, Bombs, Mutagens and Oils. There are 5 Lines to this Skill Tree. Each Line has 4 skills and each skill has several ranks, leading to a wide variety of possible builds. You will have access to all Tier 1 Skills from the start of the game, but to be able to get put points into the Tier 2 Alchemy Skills you will need to spend 8 points in this branch. 20 points will unlock the Tier 3 skills and 28 points will unlock the final Tier.
Alchemy Skills

Brewing
Enables the brewing and drinking of witcher potions.
Heightened Tolerance
Increases potion overdose threshold by 1%. Potion duration time: +5%
Refreshment
Each Potion does imbibed heals 5% of maximum Vitality. Potion duration time: +5%
Delayed Recovery
Potion effects don't wear off until potion Toxicity falls to 90% of the maximum level. Potion duration time: +5%
Side Effects
Imbibing a Potion gives 20% chance of activating the effects of another randomly-selected Potion, without additional toxicity cost. Potion duration time: +5%

Oil Preparation
Enables the creation of Oils that can be applied to swords.
Poisoned Blades
Oil applied to the blades gives a 3% chance of poisoning the target on each hit. The chance is greater the higher the level of Oil used. Potion duration time: +5%
Protective Coating
Adds +5% protection against attacks from the monster type the Oil targets. Potion duration time: +5%
Fixative
Blade Oils now have 33% more charges Potion duration time: +5%
Hunter Instinct
When Adrenaline Points are at their maximum, critical hit damage against the targeted enemy type is increased by 20%. Potion duration time: +5%

Bomb Creation
Enables the creation of handheld Bombs that can be thrown at enemies.
Steady Aim
Time is slowed a further 15% while aiming Bombs. Potion duration +5%
Pyrotechnics
Bombs that do not usually inflict damage now deal 30 damage in addition to their normal effects. Potion duration time: +5%
Efficiency
Increases maximum number of Bombs in each slot by 1. Potion duration time: +5%
Cluster Bombs
Upon detonation Bombs separate into explosive fragments. Number of fragments: 2. Potion duration time: +5%

Mutation
Enables the extraction of Mutagens from the corpses of powerful Monsters. Witchers use these to grant their bodies new abilities.
Acquired Tolerance
Every known level 1 alchemical recipe, increases maximum Toxicity by 1. Potion duration time: +5%
Tissue Transmutation
When consumed, Mutagen Decoction increases maximum Vitality by 200 for Decoction's effective duration. Potion duration time: +5%
Synergy
Increases bonus for Mutagen in Mutagen slots by 10%. Potion duration time: +5%
Adaption
Extends effective duration of all mutagen Decoctions by 10%. Potion duration time: +5%

Acquired Tolerance05 Jul 2016 15:37
Acquired Tolerance is the best way to rise your maximum toxicity. You can level it up as you get to know more higher lvl recipes. I think this is the best ability of Alchemy skills.
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