This build in particular is created for the 4th skill, Blade Storm. Keep in mind that every kill you do with this skill is considered a finisher
The 4th skill, works like this: you use it once, and you'll enter in "mark mode" where you can mark enemies, as many as you want and using a small amount of energy on each mark. Then, by reactivating the skill and by using the teleport on an enemy, you start a sequence of kills where [Ash] will teleport from enemy to enemy doing a finisher and an insane amount of damage. If you activate it without using the teleport, there will be shadows doing the damage, but not yourself.

Aura must be [Steel Charge] because it will increase the melee damage (for the finishers that we'll be doing).

The focus is on increasing the Strength to a max without sacrificing too much efficiency (reasons why I use [Fleeting Expertise] and [Primed Continuity]).
This will allow for a very strong finisher.
Efficiency must keep at a relatively high level because you will be using this as a nuker, so you'll be applying around 30-50 marks per nuke.

• We use [Rising Storm] to increase the combo and the damage done. However you can always use [Fatal Teleport] to max energy efficiency, since killing an enemy with the Fatal Teleport augment will return the energy of the teleport and start the killing sequence even if the target is not marked.

• For the weapons to use, mods that increase damage with combos (such as [Blood Rush] or [Weeping Wounds]) will increase further the damage, due to the melee multiplier that grows with each kill. Hammers have the higher finisher multiplier, so using one will be a good way of getting even a higher damage multiplier.

• Any arcane that triggers with a finisher will be useful with [Ash], since, as said before, the kills are considered finishers. So Arcane Trickery will turn you invisible (halving the energy use of marks) on every nuke, effectively making smoke screen useless.

• As an optional, you can use a zaw with Exodia Might that will trigger the life steal on the finisher, making it so you can [Recover] health in situations where there's no healer.