Kongamato's Umbral [Valkyr]

This is pretty straightforward. Activate Warcry, and then swing your favorite melee weapon faster than you can press the melee button and hope there is a stream of enemies so you never have to activate Warcry again. Works great in survival. You will also have an obscene amount of armor. I don't remember what the damage reduction was off the top of my head, but it is around 90% without Adaptation.

If you can, try to get your allies in on the fun, and let them know what they are in for.

When/if HP starts getting low, just pop into Hysteria and backhand something, then pop out. With [Blind Rage] in, you will not be in Hysteria for long.

Modifications:
I have this build copied across four loadouts, and currently the only difference between them is the [Adaptation] slot.

It can be replaced with [Gladiator Aegis], to benefit mostly from the set bonus and that tiny bit of extra armor. The Gladiator set bonus increases critical chance with combo counter, just like [Blood Rush].

Another option is [Carnis Carapace], which gives extra HP and armor, and if you use Carnis mods elsewhere, it gives some more love to that.

One more option is [Enraged]. This one is just fun. It is an augment that changes how Hysteria works, so instead of it being channeled for as long as you can sustain energy (Something that is decidedly NOT happening with [Blind Rage] shoved in there), it now lasts for a set duration, and gains 200% increased damage and critical chance. Like I said, this is just fun.

Helminth:
Replacing Paralysis with [Rhino]'s Roar is a great idea if it starts feeling like you're swinging around a nerf bat instead of a sword.. You can also replace it or Ripline with [Mirage]'s Eclipse for extra damage in the light (Or yet MORE damage resistance). I am open to suggestions here.

Weapons:
Personally, I use [Daikyu] with the mod Amalgam Daikyu Target Acquired. This gives 3% lifesteal with Nikana weapons. This only applies to Nikana, not two-handed [Nikana]. Now, 3% doesn't sound like a lot, but with how quickly you can swing, you really don't need to pop into Hysteria very often, if ever... so long as there are things to beat up.

Now this obviously means I like to use [Nikana] weapons. Lately I've been using [Skiajati], but this works with [Nikana] (Prime,) Dragon Nikana, and the Sepfahn Zaw, all of which are great weapons, especially if you can snag a decent riven.

Melee-wise, this build lends itself well to slower weapons, and you can get away with replacing attack speed mods with more damage or crit rate.