Life-Based Death's Oath Marauder (Map Farmer)

Devoto's Devotion is used for just about every line of text it has. The Dexterity helps us to get to the Freeze immunity breakpoint on the cyclopean coil, and everything else is self explanatory.

Garukhan's Flight are used for the life regen and ground effect immunity, as well as the dex we need to meet our freeze immunity. You can swap these for rare boots if you want more life, or aren't that big a fan of ground effect immunity.

Cyclopean Coil is insane on this build. With my current setup, it gives me 62% Damage, 136 max life, and immunity to both shock and freeze. I love this belt, but if you can't meet the dex requirement for freeze immunity, you can consider replacing it.

Death's rush gives us permanent onslaught in packs, armor, life, and massive chaos resist. A Staple to this build.

Watcher's eye is almost mandatory. The only required mod it needs is "you have phasing while affected by haste."

Forbidden taste - Something I should be running, but I really thought I'd of found one by now. Due to our really high chaos resistance, this is essentially an instant heal flask with no downside.

2 Jewels & 1 ring - Just pointing out that the 1 ring + 2 jewels need to have a combined total of 56% All elemental resistance.

For levelling, just run generic 2h or Dual wield melee until 62. You can grab the marauder melee starter nodes leading to RT, and that should suffice. If you have trouble with sustain during levelling, consider picking up a Thief's torment + Either Molten strike or lightning strike with ancestral call. Abyss jewels help a lot here. At 62, you can use Dark seer's (+50% Global damage, and +1 max life per character level) or 1 dark seer and a redblade banner. The Death's Oath alone will carry you through Cruel lab; I had no issues doing merciless at 68, but I do highly recommend making your first lab clear the warcry bonus (25% HP on warcry) rather than rushing the 40%
more damage passive. I had 5.6k in-game sheet on Death's Aura with a 5 link, dual seers, and no DoT Gear (No impresence, no allelpathy, etc) prior to getting the berserker bonus (just a reference). I did not run haste until I had the impresence.

Assuming 20k in-game sheet (I just need a better BoC), it sounds like this build wouldn't work to T15's... So why does it?

Well, Aura effectiveness doesn't show on our tooltip & has been confirmed to increase the DPS of Death's Oath's Aura. Just judging on how it interacts with other auras (being a more multiplier,
rather than additive), Our damage becomes 33.2k/sec. I might be wrong on this next part, but assuming despair's modifiers are multiplicative of themselves, we have 33.2k * 1.29 * 1.25 = 53.5k DPS. With wither totem, this can increase by another 90% more (I believe this is additive with depair's DOT Multiplier?) for a total of 33.2k * 1.29 * 2.15 = 92k DPS.

My blight currently has a 5 second duration, 6.6k damage/second, 5.38 casts a second... So I can stack bosses for up to 5.38 * 5 * 6600 = 177k DPS without considering despair/wither (after a full 5 seconds of facetanking, which is unrealistic). With wither and curse, this reaches 490k DPS (580k total with death's aura DOT as well). I doubt I've ever fully stacked a single mob in my life, let alone one where my curse had full effectiveness.

Overall, I have really enjoyed the life version. I would like to attempt Minotaur etc., but there are a few downfalls to build (i received my 6L Oath and subsequent 50% more damage less than an hour ago, so this could all change).

The big issue for me is the low life total, and mild sustain. the 25% HP/2sec is nice, and very useful against bosses & lab. This could be traded for the occultist regen for each mob killed,
which would feel better in large packs but worse against bosses with constant damage or rapid attacks to prevent your natural regen. Likewise, Occultist cannot do "No regen."

Multi-boss maps (E.G. Acid Lakes, with 5 tanky AF damage monsters) are rough for both builds.

Corrupted blood, IMO, needs to be nerfed. The base corrupting (max 20%/sec) is fine - I'm a bit annoyed it isnt reduced by physical damage reduction, but I can live. The problem comes in maps with added damage as X; Rallying cry will instantly stack you with 20 corrupting blood, and there is no sound/warning/etc. to let you know that you are suddenly taking 40-80% of max life as true damage every second. I've gotten in the habit of looking at my HP bar after every rallying cry, and it has helped a lot, but it's pretty dumb to me that the Added X mod also bypasses resistance. ./rant

Elemental weakness is a pain for the version I am using where I barely resist cap... Consider getting a second watcher's eye (one with Phase/Vuln, the other Phase/Weakness) to swap into whenever the map has ele weakness but not Vuln.

We also have a massive amount of movespeed, which from what I recall, occultist does not. +84% in base, +104% with onslaught from death's rush, and +164-174% with an expirementer's quicksilver of adrenaline.

I Can't really compare the damage as I supplement a lack of flat % increased via gear that occultist cannot, and occultist has other modifiers (Chaos resistance reduction, increased damage to cursed mobs) that help to mitigate the lead berserker would otherwise have with the 40% More damage.
I could be wrong, but I believe Occultist has better DPS against targets that have chaos resistance.
Berserker might have higher DPS against targets with 0. I Hate ES so I refuse to make a CI Version to find out.
I found an Occultist's Path of building on the POE Reddit - It looks like the numbers are VERY close damage wise, until the target is blighted. Due to the occultist version having 2 spreading rot,
Their damage against blighted targets is a little over 56% More than the life based version I have proposed.
With that said, if you could manage a ring with Life & 56% all resist, you could run dual spreading rot and be near identical... I'll do some more testing with this char and the tree, and find out.
TL;DR, Occultist's single target is far superior.