This is a melee focused weapon platform [Lavos] build using [Dual Ichor] (but any melee you like works here), I managed to get 268kpm over 15minutes on Mot (Steel Path) using this build. (Average KPM was 225 KPM— KPM will vary as KPM is largely dependant on tile-set).

This build isn't designed as a "[Lavos] Build" and isn't optimized for make the most out of his kit— which is why I've dumped stats I otherwise wouldn't on a "typical" [Lavos] build. The build is purely designed to turn [Lavos] into a weapon platform for the [Dual Ichor] Incarnon. It's survivability comes from health tanking through stacking damage reduction (Arcane Reaper + [Mecha Pulse] + [Umbral Fiber] + Umbral Vitality + Adaptation). I'm using Naramon along with Primary Dexterity & Secondary Dexterity to maintain combo.

The set-up uses the [Dual Ichor]'s with [Valence Formation]. I've subsumed Roar onto the build for increased damage— if copying the build, then you can subsume over either your 3rd ability or 4th ability— it's entirely up to you. If you aren't going to subsume Roar then you don't need ability strength since [Valence Formation] is fixed at 200%— therefore you should remove ability strength mods. I would instead use Primed Continuity and Constitution / [Nira's Hatred] for more ability duration (and status duration). Alternatives for even more tankiness would instead be: [Primed Vigor] (if you have it) and [Health Conversion].

Arcane [Fury] helps scale the toxin cloud damage from Dual Ichor incarnon. The second arcane is more flexible, feel free to use Arcane Grace or Arcane Strike — the triple umbral set-up is already very tanky, therefore going Arcane Fury & Arcane Strike might be the best option for you.

For the Archon Shards, I went full Tau-Red for ability duration to maximize the status duration you get from playing [Lavos] and so I don't have to reapply Roar & [Valence Formation] as often. The companion is a [Pharaoh Predasite] which uses [Anabolic Pollination] because it works to buff the damage of the [Dual Ichor]'s Incarnon clouds. (Or it did before Update 38.0— I can't be bothered to test if this is still true)

It's important to know that you don't need Umbral mods to make this build, you could instead swap:
Umbral Vitality > Archon Vitality
Umbral Intensify > Transient Fortitude
Umbral Fiber > Steel Fiber / Health Conversion or Primed Continuity

Dual Ichor
https://overframe.gg/build/828756/

Pharaoh Predasite. (For Anabolic Pollination)
https://overframe.gg/build/828759/

Paris Prime (Buffs the Predasite because of Mecha-Overdrive + Hunter Synergy)
https://overframe.gg/build/744319/