One of the strongest weapons in the game currently. The primary fire feels like a lex prime but hits a truck. Getting 12 headshots charges up it's Incarnon mode (can be shortened to about 3-4 shots with multishot). Switching to Incarnon mode with alt-fire makes it feel like a pocket Acceltra with small AOE on impact but with significant damage. This build is a raw damage non-crit build using Devouring Attrition. Why viral heat? Viral heat has the highest elemental coverage across most grineer and corrupted enemies, since both bombards and gunners share cloned flesh but have differing armor bonuses (ferrite and alloy), and are therefore both weak to viral + heat damage types. Viral status additionally multiplies all damage to health by up to 4.25x at 10 procs.

Other build options:
Crit Viral Heat Overwhelming Attrition (higher potential single target DPS): https://overframe.gg/build/315013/
Viral Slash Devouring Attrition (scales better against armor against single targets) : https://overframe.gg/build/316948

Evolution Choices

• Evolution I - Incarnon mode

• Evolution II - Rapid Wrath: +20% Fire rate. Can use recoil perk if you don’t use one of Secondary Deadhead or Steady hands, or prefer to use Lethal Momentum in exilus.

• Evolution III - Lethal Rearmament: +90% reload speed on headshot at 3 stacks. This also shortens the transformation animation to Incarnon mode from approx 3s to 1.5s.

• Evolution IV - Elemental Excess +20% status, -10% crit chance. Reducing crit chance increases the likelihood of Devouring Attrition boosted shots.

• Evolution V - Devouring Attrition: 50% chance to do 2000% damage on non-critical hits. This is currently multiplicative to base damage mods such as [Hornet Strike] and double dips the void damage instance of [Xata]'s Whisper.

Calulations of Devouring Attrition vs Overwhelming Attrition

Devouring Attrition

With no crit mods + hornet strike (2.2) + deadhead (3.6) + elemental excess (-10% crit):

• 88% chance to do no crit with 50% chance to get 2000% multiplicative with hornet strike/deadhead
  - 44% chance to do 21x(1+3.6+2.2)=142.8x
  - 44% chance to do 1+3.6+2.2 = 6.8x
• 12% chance to crit and do (1+3.6+2.2) x 2.2=14.96x

Average Damage multipliers
Body shots: 44%x142.8 + 44%x6.8 + 12%x14.96=67.6192x on bodyshots

Headshots: 75% x (44%x142.8 + 44%x6.8 + 12%x2x14.9) + 25% x (44%x142.8 + 44%x6.8 + 12%x2x14.9) x 3 x 1.3 = 135x on headshots

Now that the AOE component doesnt get headshot multiplier, only 25% of the damage receives the 3x headshot multi. Deadhead still applies 1.3x to both AOE and non AOE parts, and is also multiplicative to the base 3x multiplier.

Void damage instance with [Xata]'s Whisper
On bodyshot: 44%*142.8x21+44%x6.8+12%x14.96=1,324 x base damage x [Xata]'s Whisper % ([Xata]'s whisper double dips Devouring attrition)
On headshots and taking into account faction mods, this becomes 21,502 x base damage x [Xata]'s Whisper% ([Xata]'s Whisper also double dips 2x headshot multiplier, 1.3x bonus of deadhead and 1.55x of primed bane)

Overwhelming Attrition assuming 100% uptime at max stacks giving additive 1200% on all hits:

With galvanized crosshairs (max stacks), primed target cracker and secondary deadhead (max stacks):

• 92% crit chance to do (1+3.6+12) x 4.62=76.692x
• 8% chance to not crit 1+3.6+12= 16.6x

On headshots, tier 1 crit multiplier is 2.8(1+1(2*4.64-1))=25.984 (with secondary deadhead 0.3 and caput mortuum 0.5 multipliers additive to 2x headshot multiplier)
Headshot damage is then (1+3.6+12) x 25.984=431.3

With primed pistol gambit, primed target cracker and secondary deadhead:

• 63% chance to do (1+12+3.6) x 4.62=76.692x
• 37% chance to not crit and do (1++3.6+12)=16.6x

Average Damage Multipliers

• No headshots and running Primed Pistol Gambit (63% crit): 63%x76.692+37%x16.6=54.458 =53.126x base damage on bodyshots (lower than devouring attrition by 20%)
• No headshots and running exactly 85% crit chance: 85%x76.692+15%x16.6=67.6782x on bodyshots (Just exceeds devouring attrition).
• No headshots but running max stack Galvanized Crosshairs (92% crit): 92%x76.692+8%x16.6=72x base damage on bodyshots (exceeds devouring attrition by 35%)
• All headshots: after some maths this works out to be approximately 250-300x multiplier if all your shots are headshots (this is because the headshot multiplier is 3x but only applies to the non-AOE component, and is multiplicative to caput mortuum/deadhead (1.8x), and applies an additional 2x multiplier from critical headshots).

TL,DR:

Use Devouring Attrition if you don't want to aim at heads and just spam AOE shots (67.6x multiplier vs 54x multiplier on bodyshots using [Primed Pistol Gambit]) or want to abuse Xata's Whisper's 441x double dip.

Use Overwhelming Attrition if you want to be more precise and aim at heads for up to 2-3x higher damage (300x multiplier vs 135x multiplier on all headshots and 72x multiplier vs 67.6x multiplier on bodyshots after galvanized crosshairs stacks).

See Overwhelming Attrition build here: https://overframe.gg/build/315013/

Mod Breakdown

• [Galvanized Diffusion]: +230% multishot at max stacks, meaning you get at least 3 bullets per shot with a 30% chance for 4. This allows you to basically do 3x more damage AND charge incarnon mode 3x faster.

• [Hornet Strike]: +220% damage which is multiplicative with devouring attrition and additive with secondary deadhead but helps initial ramp up before any deadhead stacks are active. [Galvanized Shot] is not used here since it does NOT work on the AOE component (which is responsible for 3x more raw damage compared to direct hit). This is the FLEXIBLE SLOT if you use secondary deadhead.

• Primed Expel: A further 1.55 multiplier to hornet strike/deadhead and Devouring Attrition and double dips on heat procs giving them 2.4x multiplier. Use regular expel mod if no primed version as it is still a 1.3 or 1.69x multiplier.

• [Lethal Torrent]: Brings multishot to 3.9 so 90% of shots give 4 bullets, and gives fire rate (combined Rapid Wrath gives +80% fire rate total)

• Viral 60/60: Gives status chance and viral procs. One viral status gives a 2x multiplier on all subsequent hits, adding up to 4.25x multiplier at max 10 stacks.

• [Primed Heated Charge]: Biggest elemental mod bonus on pistols to multiply raw damage. Heat procs also strip armor by 50% and can stack indefinitely, which each new stack refreshing all existing stacks.

• [Primed Fulmination]: Brings the 2m AOE component to 2.9m radius to give it more spread capability, which actually increases the AREA of effect from 12.6m2 to 26m2 (a 2x area increase). This is the FLEXIBLE SLOT which you can choose to swap out for a Riven, Anemic Agility, Augur Pact, Scorch or Galvanized Shot.

• Steady Hands: Combines with Deadhead or recoil perk to give -100% recoil for laser point accuracy. [Lethal Momentum] is an alternative but this requires changing polarity.

Flexible Options
These can be added over either Primed fulmination or Hornet strike:

• Anemic Agility - can swap over hornet strike or primed fulmination for slight technical sustained DPS boost.
• Augur Pact - mostly useful for Augur set bonus for shield gating and minor damage boost
• Galvanized Shot - this is a LAST RESORT option because it is a) additive to hornet strike and secondary deadhead and b) only applies to the non-AOE component which is only 25% of total damage. This basically means galv shot is effectively only a +40% dmg per status boost and only to a single enemy at a time. You could potentially use this if offloading viral from nourish since there just arent many other mod choices.
• Riven:
  Best Positives : multishot, damage, fire rate
  Okay positives : status chance, toxin, reload speed
  Best Negatives : crit chance, zoom

Arcane

• Secondary Deadhead: Long upkeep times of +360% damage and gives -recoil and +headshot multiplier. Notably, this forces a 1.3x headshot multiplier that is multiplicative with the 3x base headshot multiplier on direct hit component (making it 3.9x) and the 1x base multiplier on AOE component.

• Cascadia Flare: Gives an extra +120% additive damage bonus compared to deadhead (i.e. a +20% final DPS increase on bodyshots) but at the loss of -recoil and multiplicative headshot multiplier (reducing final headshot DPS by 10%).

• Secondary Merciless: Doesn't need headshots to upkeep, but stacks fall off quicker, and you get a neat reload bonus that helps with transform speed. Not recommended unless you hate aiming for heads and don't own flare.

• Cascadia Empowered: Currently, Devouring Attrition multiplies each 750 damage proc of Empowered by 21 giving 15750 damage per instance (but at 50% rate per status). This is a flat damage instance blocked by armor and separate to other procs, and is a more an interesting meme option unless it gets patched. Consider using the -recoil perk instead of +fire rate if you drop deadhead).

Other Factions

For Corpus: Swap Frostbite and Primed heated charge for Pathogen Rounds to make pure toxin and add anemic agility.
For Thrax/Acolyte (without strip)/Infested: Swap Frostbite for Primed Convulsion to make Corrosive Heat and Primed Expel for Augur Pact/Anemic agility
For Angels/Eidolon: Swap [Pistol Pestilence] and [Frostbite] for [Anemic Agility] and [Convulsion]. Drop expel mod for [Accelerated Isotope].
For Murmurs: Swap [Pistol Pestilence] and [Frostbite] for [Primed Convulsion] (may need to forma even more) and [Accelerated Isotope]

[Xata]'s Whisper interaction

Devouring Attritions 2000% multiplier double dips on [Xata]'s Whisper void damage instance in that it applies twice to give a final multiplier of 44,100% or 441x.
You can see that here where Laetum can basically one-shot steel path Grineer demolysts with NO armor strip and NO priming:

https://www.youtube.com/watch?v=aFgMUfJUkK8

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