[Ceramic Dagger] transforms into Incarnon form after using heavy attack after reaching 6x combo. You can stay at 8x combo without using light attack at all by getting 100 kills with your guns. Heavy attacking while incarnon mode is active throws a projectile with approximately 5m AOE with forced impact and innate heat status. Adding a toxin mod allows you to create gas procs and adding toxin, heat and electric gives you gas electric allowing Melee Influence to be acitivated.

This is specifically for using the incarnon heavy attack projectiles to kill enemies. Grouping + armor strip is ideal to make this scale, otherwise the damage isn't very good against armored enemies. Armor strip can be applied by Amalgam [Argonak] passively or actively through warframe abilities.

At the time of testing, Condition overload works while Sacrificial Pressure/[Primed Pressure Point] DO NOT seem to apply any damage to the projectiles. Once it works, [Primed Pressure Point] is flexible over [Condition Overload]. Ability based damage buffs like Vex Armor, [Rift Torrent], Eclipse seem to work fine.

UPDATE
Melee Influence + Amalgam [Argonak] makes this even stronger for AOE nuking, at the cost of a bit of crit chance. You must slot three elemental mods to force gas + electric due to the innate heat on the projectile.

EVOLUTIONS:

Evo II: Gun and Blade : 100 IC after 100 primary kills (secondary kills work too atm)
Evo III: Adept Reflexes 20 IC makes final combo 150 after 100kills + corrupt charge, giving you permanent 8x heavy attack multiplier (but requires about 2-3s to recharge)
Evo III: Absolute Valor +30% CC sets base cc to 40%. After Sac steel + [Blood Rush] + glad might at 8x combo this gives a final CC of 356%.

Quick example of use:

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