The Flying Monkeys: Independent thinkers informed by the meta

Builds Notes (Non-Umbral Build Below):

For Slowva, hit +45% power strength then max duration. Negative range prevents Null Stars from flying all over, and combined with [Molecular Fission] maintains a permanent 90% damage reduction. [Adaptation] and [Umbral Vitality] increase the EHP pool to massive levels. Press 4, and slow the map by 75% while applying a 2x damage multiplier debuff.

[Escape Velocity] is a quality of life mod that gives the low range Wormhole a helpful and long lasting speed buff. AMD remains useful for enormous damage; its damage cap is unaffected by strength mods and its explosion radius is unaffected by range. Something as simple as a dual shot from a non-riven [Tigris Prime] will instantly hit the cap on AMD. And this combined with the 2x multiplier from Molecular Prime will instantly wipe troublesome spawns if for some reason her weapons aren't cutting it. Chances are however, if you've invested two Umbral Forma, your weapons are fine. IF [Nova] has a Helminth ability slot, it's either her 2 or 3, based on preference.

Useful substitutions include [Primed Flow] and [Quick Thinking] for [Constitution] and [Adaptation] respectively. This allows for more consecutive casts of Wormhole over a large map, or in the case of an Energy Reduction Sortie, is necessary to cast Molecular Prime. [Streamline] is useful too. Exchanging either [Augur Message] or [Constitution] trades 1.5s or 1.7s of her 18.4s total on Molecular Prime. Substituting in [Streamline] for either ensures a Zenurik Proc will refill more energy than she uses to cast Molecular Prime before the wave expires, although the above build is perfectly reliable.

With Molt Efficiency add, it now becomes the BiS second arcane for [Nova] who loves duration. Due note that although your Null Star will show 20x instances with Molt Efficiency, the damage reduction is capped at 90%. There are multiple other good options for the second arcane; select from the damage oriented ones, since extra tank is unnecessary. Other options include Acceleration, Avenger, Awakening, etc. She even uses Headshot based Arcanes well with her 75% slow. Additionally, an Aura Forma future proofs the build in case DE releases another Aura Mod better than [Corrosive Projection], but that's unlikely and expensive; the player should decide for themselves.

Slowva is exceptional CC, and extremely useful on Interceptions (slowing both the run speed to and the capture time at the terminals), Mobile Defenses, Defection, Open World Bounties--any mode that is primarily time based rather than kill based. For kill based modes like Defense, she has Speedva.

Non-Umbral build options: Substitute R8 [Transient Fortitude] and [Vitality] for [Umbral Intensify] and [Umbral Vitality]; this trades some duration, but is a 1 to 1 swap for no Umbra Formas. You could also use [Intensify] + [Power Drift] for the 45% Strength Cap. It is also worth noting that [Umbral Intensify] alone, at 44% Strength, still provides a 74% slow.