Bladed Mementum Heavy Sword
 Hive Scum Build - Warhammer 40k: Darktide 

This is an attempt to maximize the effectiveness of Bladed Momentum and Rending on the Turtolsky Mk IX Heavy Sword.

Build Core

The main combo is the new Special + Light Attack -> Heavy spam. The Special applies 10% Brittleness (for around 4 seconds) to the target, and the follow-up Light Attack has very good cleave properties and doesn’t stop on Carapace. Try fighting within a horde so you can maintain your Bladed Momentum stacks. You can reach, I believe, 57% Rending (with no Rending Stim) plus 10% Brittleness on top.

While your Rampage!  is NOT active (meaning you don't benefit from Channelled Aggression), the Push Attack deals slightly more damage to Carapace armor, so keep that in mind.

I think all Heavy Swords have the same Special + Light combo, but they have different access to the Strikedown Heavy. You can use whichever one you prefer.

Attack Patterns

• Turtolsky Mk IX Heavy Sword : Special -> Light to activate the buffs. Then either Heavy 1 -> Block Cancel, OR Heavy 1 -> Special, OR Push Attack -> Heavy 1. For groups of smaller elites (smaller than Maulers), you can spam the Vanguard Heavies combined with Push Attacks; it will do just fine.
• Turtolsky Mk VI Heavy Sword : Special -> Light to activate the buffs. Then either Heavy 1 -> Block Cancel (I personally find the block cancel on this one kind of slower or something, maybe it's just me), OR Heavy 1 -> Special, OR Heavy 1 -> Heavy 2. The only problem is the swing pattern of H2; it's very diagonal, so it can get caught on shoulders, hands, or other enemies (the damage numbers are the exact same, though). For groups of smaller elites (smaller than Maulers), you can do H2 + Lights combined with Push Attacks; it will do just fine.
• Turtolsky Mk VII Heavy Sword : Special -> Light to activate the buffs. Then either Push Attack -> Heavy 2, OR Heavy 2 -> Heavy 1 OR Special + Heavy 2 -> Heavy 1. The only problem is the swing pattern of H1; it's very diagonal, so it can get caught on shoulders, hands, or other enemies (the damage numbers are the exact same, though). For groups of smaller elites (smaller than Maulers), you can do H1 + Lights combined with Push Attacks; it will do just fine.

Loadout

• Ranged Weapon: It's whatever - I just like the Branx MkVIII Dual Stub Pistols. Any anti-special gun will suffice.
• Stim: I take the Regen Stim so I can stay in Rampage! more often.
• Blitz: Chem Grenade is here to help with really big packs of armored elites. Boom Bringer  would be nice as an anti-boss tool. Blackout grenades are quite interesting; I am contemplating switching to them just for the stagger and changing Forge's Bellow to another node.

Talent Points

• Battering Momentum and Battering Strikes are here to offset the loss of Brutal Momentum . It might be enough to use just Battering Strikes , but I can’t properly test it.
• Forge's Bellow is here to give some breathing room in a mixed horde since the Heavy Sword isn’t a stagger machine. It can be changed to Street Tough , but that can’t really be used offensively.
• A Tertium Welcome , Quick and Deadly , Forge's Bellow , Battering Momentum , Adrenaline Unbound , and Boiling Blood  are mostly flex talents that can be moved around.

I was playing with it on Auric Expeditions and a few Scab-Only Maelstroms - Carapace isn’t a problem when all the buffs are active. It just doesn’t die instantly, of course. I don’t know the exact breakpoints, but in the Auric Psykhanium, it can output around 1500 non-crit damage from a Heavy Attack in Rampage! and with 3–4 stacks of Bladed Momentum , which are not hard to maintain in a horde.

It’s nothing crazy good, far from it, but it was pretty fun fighting non-stop within Scab elite groups.