This build boost your rifle weapon gameplay.
I use it for stealpath missions like mobile defense, sabotage or survival.

You need to use your larva to catch at least 4 mobs and use Virulence on them. This will proc the [Teeming Virulence] and give you an additional 158% crit chances for 23sec.
On Exilus slot you can add more strenght to increase crit chances or [Primed Sure Footed].

You may infuse this [Nidus] with more survivability on spell n°3(gloom) or [Reach] for more primary weapon's damages (empower, [Mirage]'s spell, Energized Munitions...) on spell n°4

I use this build with a Tenet Envoy