Turn on Apply Conditionals! Switching fire modes on Overframe.gg doesn't change anything.

This build relies on mostly Fire Quills from alt-fire function in-game. Poison Quills will also do, but Cascadia Flare will be harder to stack, damage (over time) is worse, and it depends on the enemies; very situation-based.
Quills grants a guaranteed elemental proc; it does NOT directly boosts your damage.
Make sure to headshot KILL enemies, to stack Galvanized Crosshairs.

More forma can be used to add Deep Freeze and Pathogen Rounds (replacing 60/60 mods) to [Reach] 554k burst damage.

[Hornet Strike] is not added in this build for 2 reasons:

• Cascadia Flare beneficially replaces [Hornet Strike]. Why? It's easy to stack with guaranteed heat procs from Fire Quills, and grants more damage (+480% damage).
  Other arcanes, such as Secondary Merciless are harder to stack, due to the lack of early damage (assuming you're playing on Steel Path).

• Even with Cascadia Flare equipped, adding [Hornet Strike] will detrimentally give Diminishing Returns. What is "diminishing returns"? When you keep stacking one stat (+...% damage in this case), you only gain less and less additional damage.
  For example: Cascadia Flare + [Hornet Strike] grants a total of +700% bonus damage (damage mods stack additively with each other). Cascadia Flare + [Heated Charge] grants a total of +912% bonus damage (damage mod and elemental mod stack multiplicatively).
  In this case, (Primed) [Heated Charge] replaces [Hornet Strike] to MINIMIZE diminishing returns, to INCREASE bonus damage, and to INCREASE heat damage over time (with Fire Quills)!

Thank you for checking out this build. Hit the like button if you enjoy this build!