For [Inaros] and [Inaros Prime]

[Corrosive Projection]: Got nerfed but can be substituted for a better aura.

[Physique]: Maxium Health increased 90% health, not bad but doesn’t benefit for [Inaros] lasting longer in long end missions. It’s just increased health, nothing more.

[Rejuvenation]: Oh yes this mod. Specifically states +3 heal rate per second. Let me explain once [Inaros] takes damage health regeneration occurs followed by the other mods . This is the most beneficial out of [Corrosive Projection] and [Physique]. We want [Inaros] to regenerate health to keep him alive during specific missions. CP and [Physique] doesn’t do that.

Note: Using [Steel Charge] you need a great melee to steal health while using his first ability for finishers. It is possible to use Arcane [Fury] and strike. Keep in mind you want to remain tanky though during missions like Defense and Survivals.

Note: [Energy Siphon] see Slot 7. But with [Rage] or [Hunter Adrenaline] he won't run out of energy.

The Exilus adapter slot can be used with other mods but I use [Coaction Drift] (+15% aura strength and effectiveness). So experiment with this slot that you feel comfortable using.

Slots 1,2, and 3: All three umbral mods are crucial for benefiting each other. Increase in Health, str, and armor with all three Umbral mods would be 6435 which is good. Although my current build is 5225 (health) minus [Umbral Intensify] still holds strong.

Slot 4: [Adaptation] as it states When damaged: +10% resistance to that damage type for 20s and then stacks up to 90%. Types of damage include slash, puncture, impact, and so forth. Please max this mod out for full potential like the other mods mentioned in this build.

Slot 5 and Slot 6 are thinking outside the box for [Inaros] and his Prime coming out this fall. [Rage] or [Hunter Adrenaline] along with [Gladiator Finesse] or [Quick Thinking]. Now why would we use these mods. Let me break this down

[Rage] or [Hunter Adrenaline] converts damage on health to energy. Wham, Bam, thank you ma’am [Inaros] has gained energy to his energy pool (see Slot 7). Now once [Inaros]' health gets down to a low point that is when [Gladiator Finesse] or [Quick Thinking] kicks in by draining energy to stop lethal damage. Read Slot 7.

Note 1: For those with hunter builds feel free to use [Hunter Adrenaline] mod to replace [Rage].

Note 2: [Quick Thinking] mod is an excellent choice. And so is [Gladiator Finesse] since that mod is part of a set. Just pick which one you are comfortable using.

Slot 7: [Primed Flow]. Why may you ask? Check out the cost of his abilities since this build isn’t using [Streamline]. The 425 energy pool allows [Inaros] to not only cast abilities if need be. But with [Rage] or [Hunter Adrenaline] he is able to gain energy to his energy pool upon damage to health . And then [Gladiator Finesse] or [Quick Thinking] will pull from his energy pool to stop lethal damage. Keep in mind that [Gladiator Finesse] and [Quick Thinking] has a certain amount of efficiency so 125 energy pool won't be enough. Thus resulting in having a [Primed Flow].

Note 3: During an Arbitration survival my [Inaros] build (5225 health) was able to maintain health regeneration than the [Inaros] with 9000+ health. That player took time regaining health back. While my [Inaros] regained health quickly due to the combination most of these mods.

Potential mods for Slot 8:

Gladiator Aegis (+45% armor)
Primed Vigor (+health/+shields) even though [Inaros] doesn’t have shields but increases his health.
[Gladiator Resolve] (+180% health)
[Primed Sure Footed] 100% chance to resist Knockdown
Other mods that you feel comfortable using but make sure they are going to benefit Inaros survivability.

Arcanes: Grace and Guardian. Fury/Strike for using [Steel Charge] aura

Abilities: First ability is great for a quick blind and finisher while stealing health. Sandstorm is slow moving. Devour is great for stealing health but takes too long to create a Sand Shadow. Scarab Swarm takes too long to cast. Basically, if a rework happens I’d like to see a swarm of locust or scarabs to attack enemies to replace Sandstorm. And then Scarab Swarm should automatically apply like [Rhino Prime]’s Iron Skin.

Final thoughts

[Inaros] doesn’t need around 9000 healthy as I have seen in other builds. To have over 9k of health on a Warframe like [Inaros] is just for show. He is a tank and needs health regeneration to last longer in specific activities. With this build I was able to regenerate health back and keep [Inaros] alive.

When [Inaros Prime] comes out this fall, I’ll be using my build (plus umbra forma) and hopefully DE doesn’t nerf him. Unless they decide to rework his abilities then hope for the best. Either way I feel comfortable about this build for [Inaros] and his Prime.