This is a very versatile build, in fact swapping/changing the elemental mods allows you to create any combination of damage.

• The [Cautious Shot] mod can be replaced with any other exilus mod thanks to the additional capacity given by the fifth form, I personally do not recommend it, the aoe is large and due to "Heavy Caliber" the weapon is quite inaccurate, so it happens to hit walls and obstacles and end up with your ass on the ground.

Optional Mods

• "[Nightwatch Napalm]" will continue to proc heat over the duration to enemies within the napalm, allowing it and further rockets to deal more and more damage to armored enemies due to Heat proc status effect of temporarily reducing current armor. This synergizes well with this Viral build, as viral procs will increase heat proc damage and further attacks will deal increased damage due to armor reductions.
  This mod is a personal choice to add a secondary aoe effect capable of killing enemies with bubbles and shields, it can be replaced with "Bane" mods to maximize damage against certain types of enemies or with "Firestorm / [Primed Firestorm]" to further increase the explosion area.