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Introduction:

[Lavos] is an extremely versatile Warframe who is able to adapt to any situation whether you want to build him in a flexible manner to either enable both Ability and Weapons focused gameplay or choose between one of the two.

This build focuses on the former while giving you various alternative options so that you can choose depending on the situation what you would like to focus on.

Playstyle:

[Lavos] is themed as an Alchemist, and his Abilities demonstrate this granting him the powers of the elements and making him adaptable to any situation. He does not use any energy, instead going on cooldowns instead.

Each of his Abilities correspond to a specific Elemental type (Toxin, Cold, Electricity, & Heat), and can be infused into any of his Abilities (and weapons depending on if you have a specific Augment Mod) giving them an additional option on top of the corresponding innate Element of that Ability. These abilities can also be combined to create Viral, Corrosive, Gas, Magnetic, Blast, & Radiation.

1. Ophidian Bite - Toxin - This ability gives [Lavos] a way to leech Health back off of enemies, granting him an innate method of sustainability. With the Swift Bite Augment Mod, it gives you an additional method of lowering your Ability Cooldowns.

2. Vial Rush - Cold - This is [Lavos]' movement ability which scales with Range. The more range you have, the further you will slide. This can be used to apply status procs in an area around Lavos. You can also cancel the slide early by jumping.

3. Transmutation Probe - Electricity - [Lavos]' main method of lowering his cooldowns by 1.5 seconds per enemy hit. It also turns Health & Energy Orbs and Ammo packs into Universal variants.

4. Catalyze - Heat - This is where the real damage comes in. [Lavos] releases a radial (not spherical, it only extends horizontally) wave which deals damage within the specified range. It's damage increases by double per Status Effect on the enemy.

5. [Lavos] technically has a "5th Ability" with his signature shotgun: the [Cedo] (Prime). As with [Lavos]' 4th Ability, Catalyze, this weapon deals increased damage with each Status Effect applied on the enemy. It also has an Alternate Fire launching a bouncing [Glaive], basically guaranteeing Status procs on any enemies hit. The [Cedo] feels almost mandatory on [Lavos] but he is definitely strong without it as well, especially with a separate priming weapon. Still, I recommend using the [Cedo] as your Primary Weapon.

Main Mods:

We make full use of the three Umbral mods to increase Health, Armor, and Strength exponentially without any drawbacks of [Blind Rage] or [Transient Fortitude]. You can either double or triple Umbral Forma to make the build work depending on how you choose to build with the remaining flexible modding options. This alone gives [Lavos] 2,240 HP, 1,890 Armor, and 192% Ability Strength.

Both of [Lavos]' signature Augment Mods are used here with [Swift Bite] enabling us to increase Efficiency meaning we get more Catalyze casts more often and [Valence Formation] allowing us to apply whichever Elements to our weapons as we see fit for the situation.

The remaining 3 slots are adaptable depending on how you would like to play Lavos.

I tend to use either Adaptation and/or [Rolling Guard] depending on the difficulty of the missions I will be running.

For the final 2 slots we have several options:

1. Archon Continuity - This is a nice quality of life option which enables [Lavos] to apply Corrosive Status procs to enemies whenever he applies Toxin. It actually also increases Lavos' damage because of the Status Duration increase.

2. Stretch/Overextended - These are great options to increase [Lavos]' range. [Stretch] allows you to do so without any cost but only increases it by 45% whereas [Overextended] will increase it by 90% at the cost of 60% Strength. [Overextended] is generally a good option when running lower level missions where you don't mind the lowered Ability Strength.

3. Streamline - This mod gives [Lavos]' 3rd Ability even further Efficiency. This takes his Transmutation Orb's initial 1.5s cooldown per enemy hit to 1.95, bringing his other Abilities, specifically Ophidian [Bite] (allowing him further Ability Cooldowns) and Catalyze back off cooldown very quickly depending on the mob density.

4. Mecha Empowered - Allows us to increase damage by 150% against any Marked Enemy and also increasing the Status Effect spread range if using it along with Mecha Pulse Aura Mod.

5. Prime Vigor or Redirection - To increase our Health and/or Shield making us even more tanky. [Vigor] increases our Health to 2,839 and our Shield from 410 to 717 whereas Redirection leaves our Health at 2,240 but increases our Shield to 1,148.

6. Blind Rage - This will increase your Ability Strength by 99% at the cost of 55% Efficiency. If you do use this, I would recommend coupling it with [Streamline] if you want to have your Abilities up more often. It can also work with Stretch (or Overextended) if you don't mind sticking to weapons while your Abilities are on cooldown.

7. Natural Talent - Casting Speed can be a great quality of life addition to [Lavos]. I prefer to make up for this with 1 (Tauforged) Amber Archon Shard but Natural Talent is a good alternative if you don't have or want to use a Shard.

8. Rolling Guard - For those worrying moments where you need a brief moment of invulnerability or to remove any Status Effects.

Aura Mod:

Corrosive Projection is great for Armour Strip/increased damage but [Growing Power] is a solid alternative. This slot really depends on your playstyle as [Steel Charge] could also work but generally [Corrosive Projection] will be the best option here.

[Mecha Empowered] is a very good option as well, giving you more Armour, increasing with enemy density to make you more tanky. This is an especially good choice if you are running [Mecha Pulse] as the two Set mods will increase the effect range of the Mods, spreading Status Effects to a greater range as well as working well with a Companion using the Mecha Mods.

Exilus Mod

The Exilus Mod Slot is extremely flexible, especially so because of [Lavos]' Passive Ability which gives him 10 seconds of Status Immunity whenever picking up an Energy or Universal Orb. I generally prefer [Primed Sure Footed] to ensure I can never be knocked down if no Orbs drop but you can run a variety of different Exilus Mods depending on your preference such as:

1. Cunning Drift - For more Ability Range
2. Power Drift - For more Ability Strength
3. Speed Drift - For More Casting Speed
4. Sprint Speed/Amar's Anguish/Vigilante Pursuit/Enemy Radar - For Quality of Life options depending on what you feel like using.

Arcanes:

These slots are once again, you guessed it, flexible (seeing a pattern here with [Lavos]?).

Depending on the difficulty of the mission or the enemy types, you can change as you see fit.

My personal preference here is a combination of Arcane Bellicose and Arcane Blessing which synergize extremely well together.

1. Arcane Bellicose - Increases our Ability Strength by 6% for every 250 Max Health which benefits us as we initially gain of 54% Ability Strength because of our large Health pool thanks to the triple Umbral Mods. Combined with Arcane Blessing, this allows us to make full use of the possible maximum 72% Ability Strength as we kill more enemies throughout the current mission.

2. Arcane Blessing - As mentioned above, it increases our health pool which also increases our Ability Strength in line with Arcane Bellicose. Our Health is at 2240 with the 3 Umbral Mods, and Arcane Blessing can increase it by up to 1,200, taking us up to 3,440 Health at maximum stacks. This makes us a lot more tanky while also increasing our Ability Strength at the same time.

Other options include:

1. Arcane Grace - For Health Regeneration (giving us another Health regeneration option in addition to the Health we get back from Ophidian Bite)

2. Arcane Guardian - Granting us 900 more Armour increasing our tankiness.

3. Whichever Arcane mods you see fit depending on your playstyle if you'd like to focus more on weapons or abilities such as Hot Shot, Acceleration, Aegis, Velocity, Avenger, etc.

Again, extremely flexible.

Archon Shards

1. 1x Amber - Casting Speed - Feels a lot better to have at least 1 of these to increase Casting Speed, especially if you prefer to play an Ability focused playstyle. Also means you do not have to "waste" a Mod slot on Natural Talent if you like increased Casting Speed.

2. 2x Green - Additional Corrosive Stacks - Increasing the maximum amount of Corrosive Stacks will help with Armor Strip and Damage.

3. Up to you depending on your playstyle. You can add more Ability Strength/Duration with Red Archon Shards, more Health/Shield/Armor with Blue, or Secondary Critical Chance with Topaz. As you prefer!

Helminth Subsume options:

[Lavos]' kit is so synergistic that I personally prefer to stick to his base abilities, but there are some options depending on your playstyle. Bear in mind that depending on the removed ability, you will lose certain Elemental combinations for both your Abilities and Weapons.

The usual Eclipse, Pillage, and Roar can take the place of either his 2 or his 4 depending on if you want to stick to an Ability or Weapon focused playstyle.

Sickening Pulse works well with [Lavos]' kit as it will add Status Effect stacks to afflicted enemies while refreshing the timer on those effects (excluding Slash, Heat, and Toxin). It also has good base range of 48m.

End:

Hope you enjoy the build, please feel free to leave any feedback or questions in the comments and I'll be happy to help!