Raw viral heat damage variant for grineer and corrupted enemies. With current update due to armor and health changes, this scales higher than Viral Slash.

Evolutions

• Evolution I - Incarnon form - 12 headshots (less with multishot) lets you switch to Incarnon mode after alt-fire which has about 408 rounds

• Evolution II - Void's Guidance - +50% Accuracy and -50% Recoil. The combination of this perk with Primary Deadhead gives -100% recoil. If you run stabilizer in exilus as well as primary deadhead, you can run Rapid Wrath (+20% fire rate) instead.

• Evolution III - Ready Retaliation - +100% reload speed for 6s when reload from empty. This actually also affects the transformation time, cutting it down from 3.4s to approx 1.7s if you manage to reload from empty.

• Evolution IV - Elemental Excess - +20% status chance, -10% critical chance. This drops the final crit chance to 10% to synergize with Devouring Attrition and makes the final status chance approximately 70%.

• Evolution V - Devouring Attrition - 50% chance to deal 2000% damage on non-critical hits. This 2000% multiplier is currently a separate multiplier to base damage mods such as serration, deadhead, galvanized aptitude

Mod Explanations

• Galvanized Chamber - +230% multishot at max stacks

• Galvanized Aptitude - +80% dmg per status, so +320% with slash, radiation, viral and heat, or even more if you use an external primer.

• Primed Shred - gives fire rate and punchthrough

• Primed Bane of Grineer/Corrupted - additional 1.55x multiplier. If you don't like bane you can replace with a flexible option below

• Viral - Raw viral damage has a 1.5x multiplier for Corrupted. Since [Primed Cryo Rounds] exists for rifles, this gives the largest boost in raw damage which is also beneficial against overguard. In addition, a single viral status proc doubles the damage of all subsequent damage, while 10 stacks of viral multiplies all damage to health by 4.25x.

• Heat (hellfire) - optional element that applies damaging status and also strips 50% armor after 2s. Even just 50% armor strip is effectively a 3.7x damage multiplier on armor capped enemies. If you are fighting unarmored enemies or murmur enemies, you could consider swapping this to Electric.

• Amalgam Serration/Serration - can use amalgam or normal version, where amalgam gives some free sprint sprint at minimal damage loss. [Serration] is additive both Galv Aptitude and Primary Deadhead so is the WEAKEST link, and can be swapped out for any of the followiing FLEXIBLE options:

Flexible Options
1. Vile acceleration - additional fire rate
2. Primed Fast Hands - cuts a further 1 second from the transformation time (3.4s to 2.4s without Ready Retaliation active, or down to 1.5s when stacked with Ready Retaliation) and improves feel of non-incarnon mode.
3. Radiated Reload - gives some reload boost as well as radiation damage.
4. Riven - look for +ms, +dmg, +fire rate, +tox, +reload speed with negative crit chance.
5. Rifle Elementalist - boosts heat status DPS, but heat status only accounts for 5-10% of total DPS, meaning Elementalist only adds about 5% to total DPS.
6. Vigilante Armaments - slight boost to multishot

ELEMENTAL VARIATIONS

For trash clearing: Use pure blast with [Rime Rounds] + [Thermite Rounds] and add [Rifle Elementalist]
For Murmur: Use Radiation Cold or Viral Electric
For Corpus: Use pure Toxin elements

OUTDATED:
Here is a video showing the old synergies with [Xata]'s Whisper:

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