If building for the alt fire (shotgun): replace [Primed Firestorm] for fire rate or [Primed Fast Hands]
Can swap [Serration] for [Primed Fast Hands] if prefered
For corpus swap the bane for corpus, cold for 90 or 60 60 tox, and [Hunter Munitions] for hammershot.
An alt to [Primed Firestorm] is hammershot, not regular [Firestorm]. If you dont have primed faction damage mods, use the regular ones
On higher levels swap primed cryo rounds for rime rounds
For a riven you need a groll due to its dispo. The groll (for grineer/corrupted) is cold, cd, ms (reload speed/fire rate are also alr alternatives), - zoom/infested dmg (the riv replaces primed cryo rounds)
For a corpus groll, it can be tox/fr/reload speed/corpus damage, cd, multishot, - zoom/infested (the riven goes over hunter munitions/[Primed Cryo Rounds])