Endgame  ·  Level 70+  ·  S-Tier

Pestilent Swarm

Poison swarms orbit you while you dash through the map with Rushing Claw. Whatever you pass is poisoned and dies behind you.

Checked against the live guides on 2026-09-20

Season 15Patch 3.2.1Updated Sept 2026

Illustration of a Spiritborn
01 — The idea

How the engine works

Counterattack, in its Counterattack of the Swarm variant, creates Pestilent Swarms, and those Swarms are your damage. Ring of Writhing Moon makes them orbit you instead of flying off. You switch on four buffs, cast both Counterattack charges, then hold Rushing Claw and travel through the pack. Everything the orbiting Swarms touch takes Poisoning, and that damage over time finishes the job after you've gone. Damage over time can't critically strike, so this build ignores crit completely and even wears a Soul Splinter that removes it.

Who it's for

Anyone who wants the fastest Spiritborn farmer of the season that can still push close to the top. It clears every activity in the game and comes online with a single ring.

Rating
S-Tier
Difficulty
Moderate — movement takes practice
Key stat
Cooldown Reduction
Must have
Ring of Writhing Moon
02 — Skills

The bar

This is the Rushing Claw bar, and Evade stays as normal Evade. There is a second way to run the build: put Soar on the bar in place of Rushing Claw, wear Scorn of the Earth so Evade becomes Soar too, and use Widow's Web to burst the Poisoning with crits. That version needs four uniques instead of one and can't use the Splinter of Hellfire, so start here and treat Soar as the alternative.

Counterattack

Take the Counterattack of the Swarm variant. It creates the Pestilent Swarms that do your damage, and it also Weakens enemies and gives passive Dodge Chance. Cast both charges, then again whenever a charge is back. Final rank 15.

Press — on cooldown
Rushing Claw

Your movement, and the reason the build is fast. Aim far away to travel further. Start with the Evasive Swipe variant, which needs no target. It also builds Resolve. One rank is enough.

Hold — constantly
Ravager

Flurry of Claws variant. It gives Cooldown Rate, which stacks with Cooldown Reduction and has no cap, and every 10 ranks adds 1 minimum Ferocity. Final rank 15.

Keep it up
Toxic Skin

Skuttle Bug upgrade. Unhindered, extra Armour, healing over time and another way to Weaken. Final rank 15.

Keep it up
Scourge

Makes enemies Vulnerable, Slows and Fears them, and gives you damage reduction. Casting it also sets off the Balazan's Bite five-piece bonus, which is how that set works on bosses. Spare skill points go here: rank 1 at the start, 13 to 15 when finished.

Keep it up
The Devourer

The ultimate. Cast it the moment it's ready, because kills while it's active build Aspect of Supremacy stacks. It also heals. One rank.

Press — on cooldown

Passives

The build takes no Key Passive. Put one point each into Vortex and Concussive Stomp off the bar, because your Kry and Tzic runes cast them for you.

Spirit Hall

Gorilla primary, Eagle secondary. Gorilla is there for the Barrier, and Eagle for the Vulnerable damage. The secondary matters more than it looks: Harmony of Ebewaka adds your secondary hall's Spirit type to every skill and pays you damage per Spirit type, so with Gorilla, Centipede and Eagle you are scaling three tags at once. There is one temporary exception. In the middle of gearing, when cooldowns are your problem, run Jaguar in both halls together with the Loyalty's Mantle charm, which gives bonuses when both halls match. Go back to Gorilla and Eagle once Ravager reaches 30 ranks.

PickWhat it gives you
Gorilla (primary)Attacking with a Gorilla skill deals 150% Thorns to the enemies you hit and grants a Barrier for 2.5% of Maximum Life for 3 seconds.
Eagle (secondary)20% increased Vulnerable damage and +5% Critical Strike Chance. You're here for the Vulnerable damage and the third Spirit tag, not the crit.
Jaguar + Jaguar (mid-gearing only)Pairs with the Loyalty's Mantle charm to fix cooldowns until Ravager has 30 ranks.
03 — Gear

What to wear

You really only need one item to start: Ring of Writhing Moon. Harmony of Ebewaka is the big damage jump after it, and everything else is refinement.

Uniques

ItemWhat it doesPriority
Ring of Writhing MoonRing. Your Pestilent Swarms orbit around you, and a new Swarm spawns from you every 4 seconds dealing 188 to 225 Poison damage per hit. Without the orbit the build doesn't work. It does not need to be a Mythic, because the Swarm it launches itself isn't what you care about. Drops from Lord Zir.Mandatory
Harmony of EbewakaHelm. Your skills gain your secondary hall's Spirit type, and you deal 25 to 30% increased damage per Spirit type. This is the item to craft as your one Mythic. Drops from Bartuc.Core
Arioc's NeedleTwo-handed Polearm. It lets each tick of your damage over time land as a Deadly Strike for more damage. It doesn't add Poisoning, it makes each tick hit harder. Only worth wearing with a top roll on its power and good affixes.Recommended
Shattered VowTwo-handed Polearm. Enemies afflicted by more damage over time than they have Life left are Executed, bosses included. Best for pure speed farming, and hard to get.Mythic
Loyalty's MantleWorn as a unique charm. It gives bonuses when both Spirit Halls match, which is the quickest fix for cooldowns in the middle of gearing. Replace it with Protean Heart later. Drops from Bartuc.Charm
Protean HeartUnique charm. Casting a skill of a different base Spirit swaps its bonus and doubles your Core Stats for 7 seconds.Charm
Scorn of the EarthBoots, Soar version only. Your Evade becomes Soar, Soar deals 125 to 150% increased damage and triggers Vortex where you land, which groups the pack for your Swarms.Variant
Widow's WebAmulet, Soar version only. Critical strikes burst the Poisoning on the target as one hit, splash part of it onto nearby enemies, then remove the Poisoning. Drops from Duriel. Never wear it with the Splinter of Hellfire.Variant

Before they drop

You can start at level 70 with no uniques at all. Keep Stinger on the bar next to Counterattack so you have two ways to make Swarms, and stop using it once the ring and helm are in. Craft the Lore runeword helm (Ort + Sol on a white helm) and the Stealth runeword chest (Tal + Eth on white chest armour) at the Cube. Have Pestilence and Infestation in your codex before you switch. Until Harmony of Ebewaka drops, the Lore helm and Kinetic Suppression on your boots will do, and a legendary Polearm with Infestation holds the weapon slot. If you'd rather not craft Lore, a legendary helm carrying Kinetic Suppression is the other way round. Expect Vigor to feel tight at this stage.

Legendary aspects

AspectWhat it does for you
PestilenceGloves to begin with, a ring in the finished build. Pestilent Swarms deal 30 to 60% more damage, last 50% longer and spiral outwards. A straight multiplier on your only damage.
InfestationTwo-handed weapon, where the power is doubled. Swarms also deal 80 to 100% of their damage as Poisoning over 6 seconds. When Arioc's Needle takes the weapon slot, move it to the amulet for the 50% bonus.
SupremacyAmulet at first, gloves in the finished build. Kills during an Ultimate grant stacks of 6 to 9% damage, up to 60 to 90%. When the Ultimate ends you gain 5 more stacks and then lose one a second, and those bonus stacks cap at 15 in total. This is why The Devourer goes out on cooldown.
Kinetic SuppressionHelm first, then boots, and finally transfigured onto the amulet as a second aspect. Casting a Mobility skill grants Resolve, and Defensive skills cast at high Resolve deal more damage. Resolve is your defence and, through the Colossal glyph, your damage. Missing it is the main reason this build dies.
AlacrityRing, early on. Your Defensive and Mobility skills gain Cooldown Rate while moving, which keeps Rushing Claw available before your gear has Cooldown Reduction.
HasteBoots. Movement Speed that builds up the longer you keep moving. It doesn't work in town.
Debilitating ToxinsChest. 20 to 30% damage reduction, and Poisoned enemies deal 15% less damage to you. Everything near you is Poisoned, so it's always on.
Exploiter'sBoots, for pushing. Longer crowd control, and more damage to enemies while they are Unstoppable. It doesn't apply to bosses, but it pushes elites into Unstoppable sooner.

Widow's Web and the Splinter of Hellfire cancel each other

The Splinter of Hellfire removes all of your critical strikes. That costs the Rushing Claw build nothing, because damage over time can't crit anyway. Widow's Web only does something when you crit. Wear both and the amulet does nothing at all. Pick one version of the build and gear for it.

04 — Numbers

Stats, gems and paragon

Roll and masterwork toward these, in this order.

#StatWhere you roll it
1Cooldown ReductionRings, gloves, helm and amulet. Get it as early as you can, because it's all about Rushing Claw.
2Damage over TimeWeapon first, then gloves, rings and amulet.
3Vulnerable DamageGloves, rings and amulet. The Greater Affix to chase on all three.
4Poison DamageWeapon, gloves, rings and amulet.
5DexterityEvery piece. The Greater Affix to chase on pants and boots.
6Ranks to Counterattack and RavagerCounterattack on the chest, Ravager on the boots. +All Skills on the amulet.
7Maximum Life, Armour and resistancesHelm, chest, pants and boots. Balance the resistances on your gear against the ones on your charms.

Hard targets

One hard breakpoint: 30 ranks of Ravager. That gives 4 minimum Ferocity, which lets the Evolving Claws variant of Rushing Claw refill its own charges so you can hold it down permanently. Use a Polearm: a Glaive is 11% less damage and a Quarterstaff 22% less, and attack speed barely matters here. With the Prodigy's Tempo board, cast Rushing Claw three times in a row or the node doesn't trigger. There is no crit target, because crit does nothing for this version.

Tempering & masterworking

Temper Maximum Resolve stacks on helm, chest and pants, Damage over Time on the weapon, Barrier generation on gloves, Mobility cooldown on boots and amulet, and Cooldown Reduction on both rings. For Greater Affixes and masterworking, chase Cooldown Reduction on the helm, Ranks to Counterattack on the chest, Damage over Time on the weapon, Vulnerable Damage on gloves, rings and amulet, and Dexterity on pants and boots. A second aspect on the amulet comes from the Horadric Cube with a Kullean Tuning Prism, and it takes a lot of attempts, so practise on gear with no or one Greater Affix first.

Gems, runewords & Splinters

Paragon

Five boards: the Starter board, then Prodigy's Tempo, Convergence, Drive and Viscous Shield. Rush the legendary nodes before you worry about glyphs. Level glyphs in this order: Consumption, Canny, Fester, Bane, Menagerist, Colossal. Fester is a stand-in: at around 230 Paragon points swap it out for Colossal, because by then your Resolve is high enough for Colossal to out-scale it. Take every glyph to 100 first, then 150.

GlyphWhere and why
MenageristStarter board.
ConsumptionProdigy's Tempo board. Level this one first.
ColossalConvergence board. Damage per stack of Resolve, and it does work with damage over time this season. Run Fester here until about 230 points.
CannyDrive board. Second to level.
BaneViscous Shield board.

Mercenary

There are two ways to set this up. Subo hired with Raheir as reinforcement (Bastion, set to trigger on a skill cast) is the farming pair: Subo marks the next pack on your map and adds damage with Scorched Earth and Incendiary Bolt, and Bastion gives damage reduction and Unstoppable. Raheir hired with Aldkin as reinforcement (Field of Languish, on a skill cast) is the safe pair: Raheir adds All Resistance and damage through Inspiration, and Aldkin's field Slows enemies by 40% and makes them deal 20% less damage. Take Subo for farming, and switch to Raheir and Aldkin if you're dying or pushing.

05 — Getting there

From fresh 70 to finished

The ring switches the build on. Everything after that is about cooldowns first and damage second.

Fresh 70No uniques yet

Run Counterattack and Stinger together to make Swarms. Wear the Lore helm and Stealth chest runewords, Pestilence on gloves, Infestation on the two-handed weapon, Supremacy on the amulet, Kinetic Suppression on boots, Alacrity on a ring, and five Balazan's Bite charms. This is enough to climb into Torment.

First uniqueRing of Writhing Moon

Farm Lord Zir until it drops. The Swarms now orbit you and the build plays the way it's meant to. Take the Prodigy's Tempo board and its legendary node.

Build onlineHarmony of Ebewaka

Farm Bartuc for the helm. Damage jumps sharply, and Stinger comes off the bar for good.

Mid-gearingFix the cooldowns

Put Cooldown Reduction on rings, gloves, helm and amulet. The quick fix is a seal with an extra slot, the Loyalty's Mantle charm and Jaguar in both halls. Once Ravager has 30 ranks, switch Rushing Claw to Evolving Claws, swap Loyalty's Mantle for Protean Heart and return to Gorilla and Eagle.

FinishedMythic helm and the amulet

Craft Harmony of Ebewaka as your one Mythic, add a well-rolled Arioc's Needle, farm the Seal of the Diamond Mind and transfigure Kinetic Suppression onto the amulet.

PushingSwap for the Pit

Evolving Claws, Exploiter's on boots, Scourge at rank 15, and Poison Damage or Gem Strength transfigurations.

06 — Playing it

The rotation

Switch on the four buffs

Ravager for Cooldown Rate, Toxic Skin for Armour and Weaken, Scourge for damage reduction and Vulnerable, The Devourer for damage and Supremacy stacks.

Both Counterattack charges

This puts your Swarms out. Cast it again every time a charge returns.

Hold Rushing Claw

Aim far away so each dash covers more ground, and cast it three times in a row so Prodigy's Tempo triggers. The orbiting Swarms poison everything you pass. Keep moving and let the Poisoning do the killing.

Refresh everything as it comes back

Don't wait for a buff to run out. Scourge in particular goes out every 10 seconds to keep the Balazan's Bite buff running.

No charges left?

Run, and use your normal Evade. It happens, mostly when you catch a wall.

Soar versionIf you play the alternative

Soar and Evade onto packs so Vortex groups them, then Counterattack on cooldown with Toxic Skin, Scourge and Ravager kept up. Save The Devourer for big elite groups and bosses.

On bosses

Every boss fight starts at zero Resolve, so cast a few evades away from the boss first to build your stacks. Recast Scourge every 10 seconds: that is what triggers the Balazan's Bite bonus on a single target. Evolving Claws helps a lot in small arenas, because it refills its own charges as long as you cast it at the boss. Check that the Swarms are actually reaching the boss, and move closer if they aren't.

07 — Verdict

Strengths, weaknesses, mistakes

What it's good at

Where it struggles

Mistakes that ruin it

Not for you? The other Spiritborn builds: Stinger · Quill Volley.