Zealot
Hitting at least 3 enemies with an attack, increases your damage by 24-36% for 3 seconds.
35-50% Cleave on Hit. Stacks 5 times.
5-8% Strength for every 10% of magazine spent during continuous fire. Stacks 5 times.
1-4% Toughness for every 10% of magazine spent during continuous fire. Stacks 5 times.
This is a highly durable build that is very resistant towards most major threats in your average havoc matches and offers exceptional horde clear and great single target dmg, Also makes all auric games trivial
Your main source of survivability is gonna come from Stalwart + Good Balance, and my recommended curios. This in conjunction with second wind, Fury of the faithful, And in a pinch, shredder's inspiring barrage makes you very tanky in almost all circumstances, Overheads will still force you to proc until death, so try not to become a pancake.
In Aurics, you may swap out stalwart for fury rising, or completely maximise your dmg by also removing good balance to nab purge the unclean or righteous warrior, stalwart is still good in aurics however due to the fact that bosses are typical a non issue, and stalwart is up for most of the time, in havoc, something should always be dying, so stalwart is up for 95% of the mission time.
if you roll blight spreads on your havoc map, you can take off sustained assault and faithful frenzy to be able to pick up beacon of purity, this is sadly a massive decrease in overall dmg, but its still better to do that then have you and your team deal with the annoying modifier... or just yell at a chrous zealot to do that if there is one in your group.
Shredder autopistol is my main preferred ranged option for the emergency toughness replenishment it offers, and it also has really good maniac dmg, letting you pick off flamers and trappers without any problems.. also does serviceable dmg to the other special enemies, other options you can pick is agri or zarona revolver, any of the laspistols, or even the graia braced auto. (Edit: Shredder AutoPistol is getting a Dmg Buff on 25th march, and a considerable amount at that, most notablely, the finnese scaling going from a max of 0.9, is gonna be 1.5. and its base dmg is getting increased to 95 instead of 80. This Significantly reduces the time to kill for most enemys, making the shredder very reliable outside of being a toughness stick.)
Curio perks are again a personal preference, the flamer dmg reduction is great for not immediately being pressured to back peddle and instead challenge the flamer headon, in havoc however, its still recommended to back peddle and try and pick them off from afar because they outright turn off toughness regeneration unless a chrous zealot is chanting or a shout vet restores it, this is also the same logic behind bomber resistance, except in the case of pox bombers, you have so much DR that you can fight inside the pox gas without any problems, and stalwart counter acts the toughness replenishment reduction by adding an additional 2% toughness per melee kill, ontop of its dmg reduction.. you still have to deal with buffed enemys so, its not always smart to fight in pox gas if you can help it. cooldown reduction makes charge's cooldown 26s instead of 30s, which doesn't look like much, but it is very impactful. if you fear gunners, you can swap out one of the tox flamer or bomber perks for extra gunner DR, but do bear in mind of diminishing returns. also if you really dislike corruption or just want more toughness, you can swap out CDR for it.
For the relic blade, i choose the mk2 variant because it has objectively the better moveset for both horde clear and single target dmg, MK10 is just too clunky and slow to consider running and its only real strength over the MK2 is hordeclear... but the strikedowns have the windup time of a snail, and its just more boring. i value mobility over the heat management just because the extra dodge distance is more impactful then it looks, but if your comfortable with it, dump mobility for heat management, but it makes the weapon feel worse overall. Depending on where your priority's lie, you can swap out Unyielding for Carapace, but i don't recommend this because Reapers are the biggest threat to see in havoc and they typically come in packs, Same with bulwarks. If your good enough at the game, Crushers are not a threat and just require extra attention, but the option is there. If you playing Auric, You can swap out Flak for carapace, And you can swap out rampage for cranial grounding for more empowered uptime and for more consistent single target dmg with crits and headshots.