[2.3] Sea Lion in flight (dual-wield EQ Juggernaut with Whirling Blades for Uber Lab, HC/SC)

Rationale
Remember what they said about Erqi? "Lumbering as a sea lion, clumsy as a berry-drunk pigeon" he was. Let's take that literally, shall we? We want to combine two OP skills before they both get nerfed in the next patch :-) Using Marohi Erqi build-of-the-league certainly gives us the first half, the sea lion, but the pigeon part would take some work.
Earthquake needs a good one-handed mace, to be a proper sea lion, and the Pale Council provided one for me. It gives some nice mods too.
I can hear you crying "Voidheart" even from here - so another prophecy took care of that.
Then we need to fly like a berry-drunk pigeon - only really achievable with whirling Blades, so we need a good chaos-oriented one-hander with a blade. Thanks to some prophecy, I've got a Bino's Kitchen Knife. More poison, a lot of healing. Nice.
Another prophecy - and the Kaom's Way would add another huge source of healing as long as we have endurance charges (we're a Juggernaut, after all).
What else is there? Elemental damage is frightening in the UberLab, right? We don't really need much damage, so let's solve this problem once and for all with auras. All three purities, simple. If you want to, replace the Purity of Ice with some blasphemy curse for mapping or Atziri.
And the final thing: you don't get to choose the day the Uber Lab has five keys, so you need to be able to kill Izaro without damaging those Gargoyles or Leutenants. Keep a Dual Strike with its supports handy for those days.

Videos
https://secure.twitch.tv/epicfail42/v/78611503 - a Voll run with random IIQ items for +72% IIQ, +134% IIR takes about 50 seconds, including all loading and portalling back
https://secure.twitch.tv/epicfail42/v/79976983 - Atziri run, was a bit too lazy to dodge stuff, facetanked everything, so had to drink some flasks at the end
https://secure.twitch.tv/epicfail42/v/80359015 - UberLab run, 5 keys, first run of the day, so may look a bit slow

The Good
Unkillable in Uber Lab, as any competent Juggernaut, and even more so because of three Purities.
Facetanks Atziri in all phases, most map bosses (multi-projectile Piety on Malformation), etc.
Successfully completed the 6key run of UberLab with Essence and Conduits.
Very, very, very fast with whirling blades. Perfect for speed-farming Uber Lab, Voll, Atziri.
Reasonable budget, especially if you actually do prophecies. If you don't - you'll need Breath of the Council, Voidheart, and Bino's, but it's still mostly affordable.
Reflects are not a major issue (standard Lab-like mechanics with long Immortal Call on CWDT keeps you safe against phys, and you do no elemental damage).
All mods are easy - unID maps are a lot of fun.
Needs no changes for playing in softcore and/or hardcore.

The Bad
The damage is only average, not great.
Big part of the damage comes as poison (you actually have mods to support that Voidheart), so it acts a bit slower (bigger enemies tend to die behind you when you move fast). Use a loot filter with loud sounds.
The AOE is fairly small (not horrible, but nothing to write home about).

The Ugly
Regen-based build, so don't even think about bosses that have no adds (Kaom, Daresso) if the map is without regen. With flasks it's possible to do the map, but bosses are out of the question. Maybe adding some life leech and blood magic would help, but I haven't tried that yet.

Tree
https://www.pathofexile.com/passive-skill-tree/AAAABAEBAAHnBS0GxhHVEuEUIBRNFm8XLxiRGjgaVSE0Jy8oKi3SLlMx-zIJNZI26DrhOzs8LT38QT9DMUZpR35N41BHUeZV1lcNV5dYY1nzXaRfP2BBYSFjcGTnZU1mVGaeZ4BsRm20cg9ybHKpdO12rHdTeu97jHzZfXN_44CkggeDX4PMhNmE74VSi0-Mz5BVkc6Ub5Zsl3mbap7Fns2fPqLqplenMKgHrKqtCa2NsKu0L7Xytz677byfvTa-p8ABxBXE9sauxtjPftIh02_Yvdlh2sHd1eNq5FHqGO8O8kHyRfON9IP05vZI9zL60vxL_gr-jw==

Links
Note that the links are ordered by importance (if you want my opinion on a 4-link - just take first 4).
Earthquake - Less Duration - Concentrated Effect (replaced with Increased Area of Effect in maps) - Fortify - Rapid Decay - Melee Physical Damage
If Izaro is touchy today and you need to avoid hitting anything else - use in the same armor (with same colors) Dual Strike - Melee Physical Damage - Fortify - Life Leech - Added Fire - Added Chaos or something similar
Ancestral Warchief - Bloodlust (if you have Voidheart) or Melee Physical Damage - Concentrated Effect - Melee Physical Damage (if you have Voidheart) or Faster Attacks
Cast When Damage Taken (level 20) - Immortal Call - Increased Duration - Blood Rage
Enduring Cry - Portal (or Leap Slam for Labyrinth) - Blasphemy - Temporal Chains
Whirling Blades - Faster Attacks - Blood Magic
Purity of Fire - Purity of Lightning - Purity of Ice

Stats
All the numbers are for level 91.
The EQ has 9823.11 DPS and 3.09 APS without buffs.
The Ancestral Warchief has 9570.36 DPS and 3.46 APS without buffs.
Please note that these numbers do not account for EQ's aftershocks, poison, bleeding, bloodlust on Warchief, blood rage on CWDT (so, three frenzy charges), Atziri's flask, Unyielding/Unrelenting nodes...
With charges and blood rage you would see about 15-18K tooltip, with flask - about 18-22K, whatever the aftershocks, poison, bleeding and bloodlust do - I have no idea, but it's enough.
My life is 6474, not a lot, but Devoto's Devotion is worth lowering the life a bit. Life regen is 796 with charges, 317 without (there is also Bino's 200, some leech, etc).
My resists are 80/79/79/-14, chance to block is 17%, armor and evasion give 27% and 20% reduction and chance to evade (without any flasks).
Run speed is 51%, whirling blades speed is... well, high enough :)

Items


Choices
Bandits - Oak for health, kill all, Oak for endurance charge.
Ascendancy - Unflinching first, then Unrelenting, then Unyielding, and finally, Undeniable.
Leveling passive trees - not needed, just go to Duelist last - and you'll always be ahead of the enemies. Get +30 dex/int nodes soon-ish (I have no idea how to get enough int for Purity of Lightning without taking those passives).

FAQ
Q: I've heard that Earthquake doesn't scale well with attack speed, and yet you go all out for attack speed. What gives?
A: Yep, the problem is real. Imagine that you hit once (this prepares a powerful aftershock), and then, just after aftershock happens, you attack again and prepare another aftershock. Thats good, that's powerful.
Now you speed up a little bit, and your second attack comes just before the aftershock. It's too early, so no second aftershock is caused by that. Only your third attack would prepare another one, and that will happen after a pause (almost 1.5 times as late as before), so you've lost some aftershock DPS.
When you increase attack speed again - at some point you'll hit twice while waiting for the aftershock, and the situation repeats (if you hit a bit later - you get full DPS, if you're too early - you lose a bit of DPS), but even in the worst case that pause would only be half as long. The loss is still there, but it's not as horrible. While attack speed doesn't scale aftershocks, and can even cause DPS loss from them, the faster you go, the smaller is that effect.
We need the attack speed anyway for Whirling Blades, so getting more and more damage from the initial hits of EQ is a perfectly good way to power it up.

Q: Why not Unstoppable? That Ascendancy node gives huge quality of life - all those Temporal Chains, Chills, Freezes don't matter anymore!
A: You are right, actually, if you like to run - take that node. Also, take Marohi Erqi and run a standard 2H build :-) If you like to move on foot, instead of by Whirling Blades, you don't want to do all this drunk pigeon nonsence. By taking increased attack speed (through accuracy you get about 14%, I believe) you get extra travel speed and damage at the same time, though.

Q: What passives to get after level 91?
A: I think it's best to take 5 attack speed nodes near start point of duelist, then go to Ambidexterity there. You may want to get more life, a nice jewel or something else instead.
Sadly, higher levels are not fun anymore, I missed the time when 100 was achievable without health issues, so I don't think I'll ever do this now.

Q: WFT, why no Melee Physical in Earthquake in 5-link?
A: Whites and blues you already one-shot, bosses are killed by your Warchief. So, the purpose of your Earthquake is to kill whites faster so you don't have to run back for loot too often. Faster aftershocks work a bit better than stronger initial hit for this purpose, I think, so Rapid Decay goes slightly ahead. Also, for using Dual Strike to kill Izaro without touching anything else you'll need a green socket here.

Noticed a few minor problems, fixed them. Originally, I've recommended using Faster Attacks on the Ancestral Warchief. This recommendation (and my actual gem sitting there) was left from before I've got the Voidheart prophecy, and I've just noticed that's inefficient (I have a lot of attack speed, so adding a bit more gives significantly less DPS increase than huge "more" modifier on the Melee Physical support).

Before Voidheart it's like this:
Ancestral Warchief - Concentrated Effect - Melee Physical - Faster Attacks
But as soon as you get Voidheart and start poisoning and bleeding everything with your Earthquake, it's worth it not just replacing Melee Physical with Bloodlust, as I did, but recoloring and using this:
Ancestral Warchief - Concentrated Effect - Bloodlust - Melee Physical
It gives extra 4-5 thousand tooltip DPS when buffed, so, about 20%. Not too shabby.

Also, clarified that having a green socket (Rapid Decay) in your EQ is important because you need it for Dual Strike on some UberLab days to avoid killing anything around Izaro.