Welcome to my Mistress of Migraines (CC/Debuff) [Nyx] build.

After LoR was removed from the game [Nyx] seemed to practically disappear from lobbies entirely mainly because her kit's CC is now considered too situational for normal missions. However with the addition of Helminth abilities, we are now able to remove abilities that were never really needed such as Mind Control in this case (unless you want to run a build for fun where you buff up one enemy) and make more flexible builds and play styles, taking situational Warframes and adapting them to the current state of the game.

Overview of Build

This build revolves around using the [Rage] Variant of Rest & [Rage] with Psychic Bolts to stack the Defense Reduction as well as Damage Vulnerability for high damage output. If you pair this with a [Healing Return] + Status melee weapon you could sustain big time along with [Adaptation]. With so much healing from a [Healing Return] weapon you can opt for Arcanes like Arcane [Guardian] to increase your survivability even further. With this skill and weapon pairing, the build is more up close and personal so we don't need to opt for massive range.

Mod Overview

In terms of mods the aura slot is pretty flexible, most auras work there so there's no problem with aura choice except [Corrosive Projection] since Psychic Bolts already resolves armor stripping. I personally prefer [Growing Power] or [Energy Siphon]. In Exilus I do use [Cunning Drift] so I have some decent range to have a larger impact but you can swap that out for [Coaction Drift] if you really want to focus more on your aura buff. With [Pacifying Bolts] you are able to stun the enemies for a solid 10 seconds unable to retaliate, this mod is an essential part of the build. The best part about both Chaos and Psychic Bolts + [Pacifying Bolts] is that reprocing these abilities will cause the stun to go off again leading to CC chains, this is particularly useful in Steel Path to keep enemies locked down and debuffed indefinitely. To keep track of your stun duration note Psychic Bolts in this build has almost exactly the same duration as the Pacifying Bolts mod's effect.

Mod Substitutions

The umbral mods can be substituted with their non-umbral variants which will still give you 100% Defense Reduction on Psychic Bolts but do note that [Rage]'s Damage Vulnerability does continue to scale the more strength you invest in the build. The other thing with this build is that the Slow from Psychic Bolts and the Speedup from Rest & [Rage] [Negate] each other making enemies debuffed but at no speed cost good or bad.

[Assimilate] is another flex mod in this build, I use it personally because there are situations where you may need to sustain and try to mitigate as much damage as possible (i.e. fighting a steel path horde that focuses you down). Without [Assimilate], Absorb is pretty lackluster in my opinion, but if you're doing lower level missions you could potentially get away with substituting it for another mod. [Assimilate] is also a good invulnerability move given now you can roll while using it making it so you have some movement option while in Absorb.

Main Combo + Situational

This combo mainly revolves around the first two skills. Although Chaos is a great AoE CC with more enemy coverage than Psychic Bolts and Rest & [Rage] will cover the main issue that Chaos suffers from which is that is the animation cast is far too slow in comparison to the first two skills which leaves you extremely vulnerable to being attack. This creates the problem where the safest scenario would be to Absorb with [Assimilate] then cast Chaos to ensure you don't die, however if you are swarmed by a ton of enemies opening up with Chaos while in Absorb then shredding down enemies with the main combo is a viable option to lead into Psychic Bolts and Rest & Rage.

Spamming Pacifying Bolts vs. Chaos

In order to make Chaos worth using as your primary CC you would need to substitute a [Natural Talent] to achieve a consistently spammable effect but I personally feel that focusing on the Psychic Bolts will prioritize the enemies most threatening to you in your vicinity to keep them permanently stunned and debuffed which allows for melee killing enemies with a lot of damage with the [Healing Return] weapon to keep your health sustained. The biggest thing to consider in the duration of the stun for [Pacifying Bolts] and Chaos: Chaos although having a longer duration overall has a shorter stun duration (roughly 3.5 seconds) which makes the hard CC of Chaos about only 1/3 as long as [Pacifying Bolts]. Remember Chaos also makes enemies still able to attack you so the secondary effect of Chaos may not be as effective depending on your situation.

It is also important to note that Psychic Bolts although it hits less targets does have a longer range than Chaos at the cost of less targets hit. This doesn't mean Chaos is useless but rather should be used as a secondary part of your skill rotation as opposed to your main rotation since Chaos leaves you locked in animation for quite some time. Casting Chaos also costs the same amount as doing both a Psychic Bolts and a Rest & [Rage] cast so that is another thing to take into consideration when debating on which skill is more economical to use in a given situation.

The main combo being able to apply 100% Defense Reduction + 77% Damage Vulnerability and a 10 second stun in quicker succession than a single Chaos which only gives the 3.5 second stun and a soft CC for 20 more seconds at the same energy cost makes the first option much better in terms of value.

Let's talk Archon Shards

With Archon Shards being the newest way to scale your build farther with [Nyx]. These are pretty flexible but here are some buff considerations:

Crimson Archon Shard:
The weapon buffs from this are decently good and the strength will really only escalate Rest & [Rage]. Duration is good too but note that this build loses the convenience of syncing a recast with cc duration of [Pacifying Bolts] by doing this, I don't really recommend it.

Amber Archon Shard (Best in Slot):
Casting Speed*** is probably one of the best things to have for [Nyx], in fact I think this is the best option overall to slot in. Chaos has a really long cast but it is an extremely rewarding skill by cc'ing a huge amount of enemies. With enough casting speed you could even use this to permanently lock down enemies in a given area without being stuck in animation for too long.
Getting Energy Orb Effectiveness would be nice too as you could replace Arcane Energize for another arcane since energy orbs will be generating a lot more value per drop.
Azure Archon Shard:
These are all ok, Arcane [Guardian] defeats the need to archon shard armor although it will stack on top of these shards for bonus armor too in case you'd want that, shield really won't add much value, neither will health really. Energy Max could be decent but your costs are so low and you already have energize.

Arcane Setup/Alternatives + Setup with Shards

Although this is the arcane setup I consider to be the baseline setup there are other alternatives that I will get into here. Along with this I'll share an archon shard + arcane setup that I find to be the best for this build to really give it a huge amount of value.

Ideal Setup:
5 Amber shards (2x Casting Speed 2x Energy Orb Effectiveness + 1x Your choice) + Arcane Guardian/Molt Reconstruct:
With this setup you get a free [Natural Talent] and energy orb effectiveness will replace the need for arcane energize. With two energy orb effectiveness you should be able to get some strong value out of the orb pickups. With this much value you can stun and debuff your enemies, heal your allies all while casting your abilities. This setup with [Guardian] gives really strong survivability and can provide a ton of value for you constantly generating health getting good value for your energy casts. With this setup your Combo of the first three skills together would heal 228 health to you and your allies, and that's just from one rotation. Given this build was meant to spam, with casting speed you can dish out a good amount of healing.

Arcane Substitutions:
Molt Reconstruct: As mentioned above this arcane provides a lot of value and can act as a substitute for either of the arcanes in the base build. The value off of this arcane is really quite nice.
Arcane Grace: Similar to Guardian for sustain, could be a nice to keep you alive if guardian isn't your preferred arcane.
Arcane Barrier/Aegis: Could be nice for sustain and additional gating but really don't see much value in using it to take up an arcane slot.

Focus School

Focus schools are completely a preferential choice. Zenurik is what people would normally go and for standard setups I'd probably say it's alright for energy economy. For the full setup however I'd recommend the reader to look into Vazarin. The main reason behind this is the natural synergy between this build and Molt Reconstruct. By getting Affinity Range bonus you can increase your healing radius of Molt Reconstruct. On top of this with skills like Guardian Shell (Base 500 damage shield for players affinity range) and Squad Regen (+10 hp/second) you can not only act as just a CC frame but a passive healer too for your whole team.

Support Variant
If [Rage] isn't for you and you want to commit to a more support role while still heavy casting then I'd presonally recommend swapping [Growing Power] for [Power Donation] and [Rage] for Spellbind, providing this means that [Nyx] can heal, CC, status immune allies, and give ability strength to allies, all in one making her a true force to be reckoned with.

That's all!

This build is pretty cast heavy but the fun part about it is the skill animations are fast making it seamless with melee/weapon combos. I've enjoyed this build in Steel Path quite a bit and it does hold up for me being a fun build. Along with the amount of extra versatility you can get with the components mentioned above.

This is my first public build guide and I hope this guide was informative and the build proves to be both useful and fun. This new dynamic kit on [Nyx] in my opinion opens up for a lot of possibilities and engaging gameplay and with this she can reclaim her throne as the CC Queen.