Always aim. Always aim for the head.

Replace Riven with [Hollow Point].

Weapon has a semi trigger, so it shoots as fast as you can click. [Lethal Torrent] gives us more multishot, but the fire rate is somewhat redundant.

Uses fire damage to maximize Cascadia Flare. The fire DoT can proc Chamber Cascade on tick.

As an alternative, if you wanna rock with the headshots, replace Riven/[Hollow Point] with [Pathogen Rounds] and Cascadia Flare with Secondary Deadhead. Gas damage is also a DoT combined with an AoE effect for more chances to proc the weapons gimmick.