I suggest using:
4 Amber Archon Shards with ability cast speed. (if you dont have access to shards, you might want to use Natural Talent instead of Transient Fortitude)
1 Violet Archon Shard with melee critical damage.

OVERVIEW/PLAYSTYLE:

3 to gain 50% max energy (costs 50 HP).
4 to gain full hp (tap if close to death, hold for damage and slash procs to many enemies)
1 to deal massive damage to enemies affected by slash (hold it after getting the shield thingy) this can NUKE
2 (Gloom for cc and another way to gain health for 3 and for your allies)

Using 3 and 4 on switch can basically make you invincible and give you FULL mana if you just tap 3, 2 times then you can hit 4 or use Gloom to regain health.

Thanks to this ^ you can afford having [Blind Rage] and Gloom active. Since ability casting speed is way cheaper in shards (only 2 standard shards to gain the same as a mod, now compare that to ability duration, strength, energy storage etc.) For this reason I swapped [Blind Rage] out with Natural Talent.

If you are playing lower levels. You could forma Power Drift and Stretch. Then REMOVE forma from Blind Rage/Transient Fortitude (so just forma the "v" (Madurai )into a "-" (Naramon) and exilus (total of 2 forrma more). Then you could slot [Quick Thinking] on there. This mod gives about 2.000 EHP with full mana, so thats about 1.000 EHP from just tapping your 3. I know you have 1/2/4 to heal anyways, so theres really no point. However having to spam abilities all the time (also to keep up Gloom) can get a bit annoying, and for lower levels theres really no need. This is just something I was thinking about. It also helps to counter those Eximus that arent effected by Gloom and other abilities.

Use a Viral primer (I like [Epitaph]) to gain more value of the slash procs (or Nourish subsume, but I prefer primer to have the Gloom, yayy)

Need Augur mod on weapon or sentinel, for being able to shield gate with ult. (It's on my Epipath build)

[Steel Charge] or [Swift Momentum] for use the with [Garuda Talons].

ABILITIES:

Gloom, Terrify or Nourish. AKA: Crowd Control, Armor Strip (damage boost) or Viral + more energy (damage boost + energy bonus)

COMPANION:

[Diriga] for priming and enabling [Archon Stretch]. My Diriga Prime Build AND Weapon (Viral+Heat/Archon Stretch Procs)

FOCUS SCHOOL:

Madurai for casting speed

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