What is this weird build?

You're an unlimited ammo, aoe healing, energy giving warfarme that is fairly tanky, has rather good crit buffs and a small status cleanse field while being permanently invisible and hitting like an absolute truck.

How it works?
Use your stealth arrows to clear status effects.
Stay in prowl for headshot damage bonus
You can ignore almost every spy missions mechanics thanks to [Infiltrate].
Use [Glaive Prime] with navigator to one shot most special mobs at max stacks or normal steel path mobs without it
For your primary and secondary you can pick what ever you want, anything that isnt silent I'd suggest using [Hush], even the [Ignis Wraith] is nuts with this just because of the headshot damage increase if you want mob clear, though single target I'm loving the [Cernos Prime].

Only changes I'd suggest with this build, you dont need umbral mods, these are just overkill so for a cheaper build run:
[Transient Fortitude] (Feel free to swap this for umbral fibre in the regular build if you want but the prowl energy drain is a bit of a downer but youll hit much harder with navigator)
[Vitality]
[Streamline]

You can also change the aura to what ever you want and I often switch between [Preparation] and [Power Drift] for the exilus slot depending on how lazy I'm feeling.
The other option if you want to be really supportive is [Growing Power] or [Power Donation].