INTRODUCTION

Felarx is a full-auto projectile shotgun that feels like an automatic Exergis, that transforms into semi-automatic dual pistols. We will mostly be using the Primary Shotgun mode due to the higher base damage, innate multishot and better feel of full-auto trigger, but the build would also work well for the incarnon mode. The non-incarnon mode also has infinite body/enemy punchthrough.

Due to the Devastating Attrition perk giving 2000% damage multiplier on 50% of non-crits, we build Felarx for a raw damage non-crit build and take advantage of shotgun's access to TWO Primed elemental mods ([Primed Charged Shell] and [Primed Chilling Grasp]). You can either build for raw Viral + Electric or raw Corrosive + Cold. Corrosive has a 50% bonus against Grineer while Viral has a 50% bonus against Corrupted enemies, however Corrosive Cold can be used alongside the common subsume Nourish to get Viral Corrosive Cold. Viral or Corrosive Heat is a slightly less effective alternative due to lack of primed heat mod and relatively low status chance.

An alternative playstyle that I prefer, that may not be for everyone, is to use a secondary or melee primer and constantly swap to reload (only 1.7s for full 13 clip reload with Evolved Autoreloader perk) and prime for mega boosting the multiplicative [Galvanized Savvy].

EVOLUTION CHOICES

1. Incarnon Form : Land headshots to build up charge.
2. Frictionless Flight : +50% Projectile Flight Speed OR Kinetic Baffle -50% recoil (combines with Deadhead to be 100% recoil reduction). This is mostly personal preference, if you are okay with the minor recoil it has.
3. Evolved Autoreloader: allows you to bypass the insane reload time, allowing full reload in 2s of swapping weapons (or just 1.7s with two Synth mods). Combine with a Primer or use a melee to quickly switch between weapons. Mounting Momentum is an alternative that gives +10% fire rate for each shell reloaded. If you reload 13 shells from empty, you can get up to +130% fire rate for the next 13 bullets, but the total reload is still about 3s long. If you want this, drop shotgun spazz for primed tactical pump. The non-incarnon form actually has infinite body punchthrough, making the dual mode chamber perk useless.
4. Wracking Wrath: +20% status chance, -10% crit chance. Improves chances of Devastating Attrition proc
5. Devastating Attrition: 50% chance to deal 2000% damage on non-crits. Presumable similar to Devouring Attrition, being multiplicative to base dmg sources.

MOD CHOICES

• Galvanized Hell : +230% multishot at max stacks,
• [Galvanized Savvy]: +80% dmg per status, so potentially +400% dmg after 5 statuses, or even more with priming. Apparently multiplicative with +dmg sources like Primed Point Blank and Primary Deadhead
• Primed Ammo Stock : turns magazine size from 6 to 13. If you reload from empty, you can gain +130% fire rate from full clip.
• [Primed Tactical Pump] : cuts long reload speeds. Use [Shotgun Barrage] instead if you use Evolved Autoreloader perk (stack with Synth set for about 60% reload per second of holster, or basically full reload in 1.7s upon switching to a primer or melee).
• Shotgun Barrage: gives fire rate, can swap out if you have external fire rate e.g. Reinforced Bond.
• [Primed Cleanse Grineer] : Multiplicative 55% to other +dmg sources. Flexible for Primed Point Blank (only slightly worse overall DPS, best used for Acolytes/Thrax/Factionless or if you don't like swapping faction mods).
• Primed Charged Shell/Contagious Spread/[Primed Chilling Grasp] : maximum elemental damage for raw corrosove + cold. Switch order to make viral + electric if desired, or add Incendiary Coat or Blaze over Primed Chilling Grasp to make Corrosive/Heat. Add [Incendiary Coat] over [Primed Charged Shell] and reorder mods to make viral heat. [Primed Chilling Grasp] is flexible for Chilling Reload. Contagious Spread is alternative to Toxic Barrage (needs more forma for tiny damage boost). Can use non-primed versions or 60/60 versions of any elementals if you don't own them or can't fit them.

FLEXIBLE OPTIONS

• Primed Cleanse: multiplicative bonus against specific faction, use this for endurance disruption over shotgun barrage especially if you have external fire rate
• Blaze: gives +heat and +damage

Arcane
Flexible choice

• Primary Deadhead : +360% dmg after just 3 headshot kills which multiplies with Galv Savvy, recoil bonus and extra 30% headshot multiplier.
• Primary Merciless : +360% dmg but needs 12 kills and drops stacks quickly, ammo maximum and reload bonus go very well with [Felarx]

Other factions
For Murmur: make RADIATION + COLD.
For Index: Make MAGNETIC

Riven
A riven is usually NOT recommended due to the very low disposition meaning most rivens you roll will simply give you less DPS than other shotgun mods.
Desired positives include +dmg, +multishot, +fire rate, +magazine capacity, +element and desired negative is -critical chance.

SYNERGIES

Magnetize and [Xata]'s bubbles synergize with the infinite punchthrough property

OUDATED AS [Felarx] NO LONGER DOUBLE DIPS [Xata]'s WHISPER:
Demonstration of using a primer, autoreloader and synergy with [Xata]

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