
The manuscript for this potion is found on the following merchants: Keira Metz and Otto Bamber.
South of Hierarch Square, and across the canal.
Novigrad- Sold by a halfling herbalist in Novigrad. For example Igni will gain a 100% chance to burn it's victims.Black Blood Witcher's blood injures Vampires and Necrophages when they wound him. Having such high sign intensity will cause signs to have devastating effects. Even so the damage boost will be enormous. Like most effects that boost stats the skill will only take base damage into consideration and ignore all other boosts. Since the effect increases both damage and sign intensity it works best with hybrid builds relying on both combat and signs. Another skill worth using along with the mutation is Heightened Tolerance which will eliminate the damage caused by high toxicity. When all boosts are put together it increases the toxicity pool capacity up to 327 (332 in New Game +) increasing the limit to 245.25% (249% NG+)
The pool can be increased further using Metabolic Control and/or Manticore School Gear.
At maximum Acquired Tolerance can increase the toxicity pool to 267 which brings the limit up to 200.25%. Thus even if one does not normally use alchemy skills in their build it can still be added for maximum benefit. The mutation works extraordinarily well with Acquired Tolerance, which not only increases the toxicity pool but also, being a skill from the alchemy tree, can be inserted into the additional slots. The description can be misleading as the 75% limit applies only to the base toxicity pool, thus using effects that increase the pool capacity will also increase the limit. Each point of Toxicity increases damage dealt by swords and Sign Intensity by 0.75% (to a maximum of 75%). 3 × Greater green mutagen Euphoria is a mutation in the Blood and Wine expansion, which allows adding abilities from the Alchemy tree to the additional slots.