INTRODUCTION

This is a typical gloom [Banshee] (or gloomshee) build that combines the extreme slow offered by gloom to lengthen the stun of silence while allowing you to carefully target sonar spots for extreme damage. This build varies slightly by giving up maximum base slow in favour of more survivability in the form of [Rolling Guard] + shield gating (with two augur mods). Maximum slow can still be reached with additional equipment like pax bolt arcane and [Growing Power]. Silence has an innate stun duration of 2s, which can be extended up to a maximum of 40 seconds at 95% slow.

Why both augur mods?
This is so Sonar can completely fill shields (generating 80 while holding decaying dragon key) in one cast for most effective shield gating, while still having decent efficiency.

BUILD SPECIFICS

Duration
Positive duration gives decent sonar and silence durations up to 38s, and helps reduce gloom drain costs.

Efficiency
Positive efficiency reduces gloom drain costs but is also important in reducing the cost of 2 so you can spam it to stack sonar spots and shield gate on demand.

Range
Positive range is nice to [Extend] the range of gloom, but too much range is actually detrimental for silence since the stun only lasts 2s outside of gloom and about 8s in gloom, and you need enemies to exit then re-enter silence range so they can be restunned. This is made easier by having a lower range. Since silence has a longer range than gloom, enemies will always be subjected to silence first before gloom meaning gloom has a slightly reduced effect on the stun, particularly if you travel slowly.

Strength
Strength affects both the sonar multiplier and gloom slow so we do want this as high as possible without losing too much functionality. At 223% strength, we hit 78% slow (silence stun 9s). If you own a kitgun with pax bolt, you can get a headshot kill to gain 30% str and snapshot this strength by casting gloom to hit 88% slow which is enough for most content (silence stun 17s), or simply run Molt Vigor/Augmented to [Reach] slowcap.

Flexible slots
[Rolling Guard] is always preference dependent. If you are confident with shield gating without this, it's fine to swap out for more strength or duration. I feel it's still the best option particularly if you are nullified/disrupted or run out of energy since [Banshee] is a glass cannon.

If you want to stealth level weapons or focus farm in Adaro, replace [Rolling Guard] with the [Savage Silence] augment.

The augments [Resonance] and Sonic Fracture are both flexible options that can be placed over augur secrets or umbral intensify.

Exilus
Preparation - best option for speedrunning exterminates/lich missions, can keep mod at rank 8 since your energy will start at max
Power drift - to get higher slow
Primed sure footed - best option for everything else, particularly if you plan on using explosives

Keep in mind Sonar is like inbuilt radar so you won't need to slot enemy radar or vigilante pursuit.

Aura
Brief respite - to allow sonar to reset shield gate along with augur mods

Arcanes
Energize is nearly compulsory to sustain gloom (at least rank 3).
Either Molt [Vigor] or Molt Augmented to provide strength to hit max gloom slow (need 272% str), and boost sonar

Since headshots become much easier with gloom, arcanes that trigger on headshot are good:
Consequence - faster parkour
Pistoleer - ammo efficiency
Precision - pistol damage
Rage - primary damage

Archon Shards
2 Amber Cast speed shards makes spamming of Sonar and recasting of Silence extremely quick.
Put rest of shards into strength as preferred.

ARSENAL

Companion
[Dethcube] with Energy Generator is the recommended companion so you are able to generate an energy orb roughly every 10 kills. Build: https://overframe.gg/build/224301/dethcube-prime/cube-of-deth-health-energy-orb-generation/

[Helios] is also a great sentinel when not using an armor strip subsume. [Helios] can use [Vicious Bond] to give passive AOE armor strip as enemies get damaged by abilities and can also use Seismic Bond which gives a free 30% efficiency with near continuous uptime. Helios Build: https://overframe.gg/build/542050/

Secondary
Pax bolt is great for giving a bonus 30% strength outside of mods, which can be snaplocked by gloom. Note that channelling abilities like gloom do NOT snapshot efficiency. This can be used on secondary kitguns like tombfinger, catchmoon or gaze.

PLAYSTYLE

1. Activate both gloom and silence (optional - get headshot to activate pax bolt for +30% str +/- [Growing Power] for +25% then activate gloom for higher slow values)
2. Keep silence active at all times for stun and preventing special enemy abilities
3. Whenever shields break, roll and cast sonar to regenerate shields completely to reset shield gate
4. Stack multiple casts of sonar when fighting an enemy with damage resistance e.g. lich/sister/acolyte

Here is a video demonstration of the playstyle:

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