History of Sympathetic Arsenal

Sympathetic Arsenal is a Trait perk. When you reload right after a final blow, your stowed weapons reload too, so a backup gun is ready when you swap to it. The trait also adds +20 Reload Speed to the weapon it is on.

It rolls on a wide range of weapons, including Imperial Needle, Trustee, Enyo-D, The Third Axiom and Blowout. It is most useful on a weapon you swap to often, since it keeps your other gun topped up after kills without any extra steps.