The skills which i have used are in the following picture :

• Water hag decoction: Damage dealt is increased when vitality is at its maximum.

• Wyvern decoction:Works well with Quen sign, as attacks absorbed by the shield will not cause the damage boost to reset.Since the boost requires avoiding damage it can also work well with Water hag decoction and Invigoration as long as Geralt remains at full health.

• Ekimmara decoction: Damage dealt to foes regenerates vitality.

• Arachas decoction: Less weight means less damage. Lower your inventory weight and wear lighter armor . There is an ability or an enchantment that makes all armor treated as light armor so that could go together

Also i suggest you to use the superior white raffard

We will use the Grandmaster legendary armor set : Armor,gloves,pants,boots and crossbow.

make sure to use levity enhancment with the ursine armour will work with cat school techniques. Therefore increasing fast attack power by 20% and critical hit damage by 100%.

• Silver sword: Aerondight which i believe is the best silver sword in the game

• Steel sword: Toussaint Knight's steel sword

make sure to use Invigoration enhancment with both swords It works well with water hag decoction as both require Geralt to remain at full health.

I found out that the most effective bombs are the Northern wind and the moon dust

EUPHORIA is still the best and the most op mutation in the game

• Each point of Toxicity increases damage dealt by swords and Sign Intensity by 0.75% (to a maximum of 75%)

• 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. Thus even if one does not normally use alchemy skills in their build it can still be added for maximum benefit.

• At maximum Acquired Tolerance can increase the toxicity pool to 267 which brings the limit up to 200.25%.

• The pool can be increased further using Metabolic Control and/or Manticore School Gear. 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+)