Including this build here for its amazing synergy with Osteo Striga (and Thorn, but we’ll use Osteo). Necrotic Grips on their own, are an OK exotic. They grant a small increase to airborn effectiveness of your weapons of sorrow (Osteo/Thorn). More importantly, it now applies poison to each melee attack, charged or uncharged. The poison damage dealt to enemies increases each 0.5 seconds while they take poison damage. If a poisoned enemy dies, they will spread the poison effect within a 5m radius around them. What’s interesting with the Osteo Striga + Necrotic Grips is the poison effect that would normally only effect melee attacks, is not applied to all the Osteo bullets. Effectively, you can spread poison damage from a distance to every enemy you damage. They will also spread the poison to everyone around them. This creates an amazing synergy between exotic and weapons alone. This paired with an oppressive void build makes for one of the best builds available.
Aspects
Feed the Void is a pretty simple aspect. All ability kills will now grant Devour. Devour both heals you, and generates grenade energy for each enemy killed. Additionally, every enemy killed while Devour is active, will extend the duration of Devour. Child of the Old Gods is another great aspect to help with our ability regeneration and to weaken enemies. When using your class ability (rift) it will create a void soul. This void soul will seek out enemies when you damage them with your weapon. The void soul will then fly out to them and drains them, doing both damage and weakening them to your attacks. While an enemy is being drained, you gain increase grenade and melee energy. If you kill and enemy that is being drained by the void soul, you also gain class ability energy.
Fragment
Echo of Remnant is a simple fragment, it increases the duration that your Vortex grenade lasts. Echo of Leeching is helpful towards our survivability. It starts health regeneration on every melee final blow for yourself, and nearby allies. Echo of Cessation will create Void Breaches when you defeat volatile enemies. Void Breaches provide class ability energy when collected. This paired with echo of instability will provide a constant stream of these void breaches. Echo of Instability will grant all your void weapons with Volatile rounds when you defeat enemies with your grenade.
Feed the Void & Child of the Old Gods
Echo of Remnant
Extends the duration of your Vortex Grenade
Echo of Leeching
Melee final blows heal you and nearby allies
Echo of Cessation
Defeating volatile enemies will create Void Breaches.
Echo of Expulsion
Void ability final blows causes enemies to explode.
Healing Rift
Provides a steady stream of healing while standing in it.
Burst Glide
Best overall movement jump for the Warlock.
Pocket Singularity
Ranged melee that makes enemies volatile and pushes them away.
Vortex Grenade
Best grenade to use with this build. Lingers on the ground and weakens enemies.
The best exotic for this build. Being a weapon of sorrow, it will activate Necrotic Grips exotic effect at range. Further to that, Osteo has its own poison damage it can apply from a distance, doubling up on the poison effect. This creates a very powerful damage over time effect utilizing the poison. This allows the weapon, and build, to be very effective in just about any difficulty of the game.
Funnelweb is a strong option as a void SMG. It offers competing perks that allow it to output great damage.
A very strong wave frame grenade launcher. It can have the perk destabilizing rounds, which makes enemies nearby volatile.
One of the best grenade launchers available. Doubling down on the void weapons to maximize damage.
Destabilizing Rounds // Demolitionist // Repulsor Brace
Any weapon with the above perks will benefit the build and work with it. Destabilizing Rounds will make enemies nearby to the enemies defeated Volatile. Demolitionist increases grenade ability regeneration for each final blow. Repulsor Brace heals your and applies a void overshield when you defeat enemies affected by any void debuff. This includes suppress, volatile, or any weaken effects.
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Kinetic Siphon
Use this Siphon if you are also using Osteo Striga. Otherwise, match the primary ammo weapon type you use.
Ashes to Assets
Generate super energy on Grenade kills.
Font of Wisdom (opt)
Increase Intellect for a short while.
Firepower
Grenade final blows create Orbs of Power
Impact Induction
Causing damage with your Melee attack will reduce your grenade cooldown
Grenade Kickstarter (opt)
When using your grenade, generate grenade energy based on armor charges.
Element Resistance
Use the appropriate element resistance that corresponds with the activity you are doing.
Kinetic Weapon Surge
Use if you want Osteo to do more damage. Otherwise, match your heavy weapon element type.
Innervation
Reduce grenade cooldown with each Orb of Power pickup
Absolution (opt)
Reduce all ability cooldowns with each Orb of Power pickup.
Time Dilation
You can retain armor charges for a longer period of time
Bomber
Reduce your grenade cooldown when you use your class ability
