Level 100 Hybrid MoM Crit Rolling Magma Inquisitor^3.21

Notes

EDIT 1: Prismatic burst doesn't work on spells, so ignore any mention of it. You can try to fit it on Shield Charge 4l, and RF 4l for mapping fast, and use Vaal Firestorm for any singletarget boofing
EDIT 2: With Skin of the Lords, use Empower over Cruelty. The bonus skill level makes it a +28 and gigabuffs the damage by almost double.

Uniques: and Gear:
Use Sporeguard until Skin of lords, with any keystone on tree. It saves you 1 point max. Can experiment with Eldritch Battery or Supreme Ego, no other keystone is worth it.  (price - 150c, end of 3.20)
Use timeless jewel helper to find: Fire damage, spell damage, life, cast speed. projectile damage, The surrounding fire notables are good, but for my current progression I did not want to sacrifice life nodes for them
The Fire Walker leech actually helps quite a bit.
Did not previously use The Magnate - 3div Warlord belt for health/regen, but Magnate is quite good. Use it until a high-end abyssal belt
Rathpith's is our entire build.
Ralaketh's Impatience will be used until Tailwind boots - and may still be better, depending on how you feel. It activates during our hardcasting.
Watcher's Eye - you have a lot of leeway on this. I got lucky with a 2div roll for triple value. Any vitality mod works, any determ mod works, Anger is high damage boost, Precision is quality of life. 
I technically barely get value from mine when I have Determ on for hard content.
Forbidden Flesh/Flame - This is tough to say. Our rare jewels give a lot of %max life, and Inquis has the most expensive allocations. Pious Path is lowend at 1div each. 
Augury right now gives 500k dps, and each jewel gives 100k-200k+100 life. 
If you can get a 5th allocation, go ahead and do so, but this talent was not worth it when I was still playing at 1.5mil pob dps. Now that we can get 4mil-5mil easily, it's much more enticing.

Resistances are entirely dependent on progression. Take what you need and convert with harvest as you go. Get as much chaos res on gear as possible. 
I am not changing my entire character's POB around to inflate chaos res. This guide is based on my lvl100 end of league snapshot and adjusted for new tree and skills.
DoTs don't matter anyways, you out-regen them.
I don't care about spell suppress, but I'm sure it would be nice. I valued raw life/regen.

Rares:
You want +1 fire spell from amulet and weapon. Any other sources work too. These were cheap for me. 2div dagger 1div amulet at league start.
Stat priority is Life>Chaos/Resists>Strength>Crit>cast speed>Life Regen>>damage recoup>>anything else
You will need one or two high dex rolls. If you land good rolls, you can take out 1 dext node on tree.
I bought all my gear, no insane crafts. Total budget is probably <15divs for a lvl100 mapper.
Weapon - buy as you go. Find +1 fire gem mod, and 5 damage mods. They all do roughly the same dps. use the POB Upgrade finder as your budget allows. I only upgraded weapon twice
Jewels - I didn't start using a cluster until after lvl 95. Tree was bad and i didn't realize the power. Definitely run at least a medium cluster, and look for damage stats + %max life on every jewel.
These are what make them outperform Forbidden flesh/flame. 100k-200k dps per jewel is average for <1div each.
Health is actually a little higher, not sure if it's counting %20qual on jewelry.
CHANGES I would make: min/max gear better. Double damage on weapon. Min/max resistances, plan ahead of time. Invest more into gloves/helm/amulet. Chase t1 fractured Vermillion rings. Tailwind is luxury, I used Ralaketh's for a long time.

Use whatever flasks you want - Bottled Faith is luxury. Keep 1 high/instant life, Runi's, Diamond, and Quicksilver. 5th doesn't matter.
Unsure about charges. Endurance comes from Enduring Cry, i get power charges somehow, but not sure where. If you can find a way to use them, go ahead, but the cast speed from Frenzy charges would be worth more than Powers.

Pantheons don't matter much - change as needed. Araklaai might be solid, never tried.
Pantheon swap+sibyl's for reflect immune
Kill alira for resist+crit, could take 2 points. I never did the math. With Magnate, you can probably kill Oak.
Lab enchant: Any rolling magma mod works, I got +40% damage on my first lab and decided I'd stick with it all game.

For the tree, take out life nodes and cluster until you get past lvl90. Excess life+cluster is 13 points. Max resists can be removed also - they removed the Mastery i had allocated.
If you think the levels are too high, don't worry - you'll level very fast, and you only get stronger. There was no "weak point" from when I started with rolling magma, all the way to end game.
6 Life mastery nodes is not worth it. The new 3 life masteries do nothing for us. I cannot figure out how to make Petrified blood+pain attunement work with this build, but it might be lols.
Hiero version: I can't figure out how to make mana worth it, so you're running 3 ascendencies. Inquis tops out better with much better regen.

High block, regen, life, ES is our defense layers. From budget to high-end, you will never die in maps. This build blasts breaches, abysses, harvest, beyonds, blight maps, strongboxes, legions.
I'm usually a MAX lvl92 by end of league player, and I took this homebrew all the way to lvl100 since it was so good at aoe and not dying. Best build I've played in a long time and made me realize the fun of not being metaslave.

eHP is hard to calculate with our high regen. Your health does not bounce much, it remains at/above 80% at all times even when standing still spamcasting. I was able to facetank uber elder beams.
Hierophant tree was not worth it. If budget allows, pick up Forbidden flesh/flame for arcane surge node, but Augury is roughly the same dps.

Rolling Magma doesn't instantly screenclear, but it's pretty close. Carpet-bombs their entire path, t16 40% delirium packs die in 1-2 casts.
USE Cruelty until Skin of the Lords, then switch to Empower. The interaction is too strong.
Use Pinpoint over LMP/GMP. It's better and way smoother for Single target encounters. You'll always be moving and casting, killing so fast, you'll always be shooting 4 projectiles in maps.
Awakened Spell Cascade isn't necessary - use regular or faster casting. I lucked out while Beast gambling (which I recommend once you have a 10-15div stock, buy the beasts for 80-100c max, and 10c awakened gems)
Explosions come from Sporeguard. Still think Skin of Lords will outperform, but i went starting-100 with Sporeguard. Once your damage is >1mil you don't need the tiny chaos pops
Flame Wall adds a little bit of damage and is cool
Precision/Vitality reserve our health
Anger/Determ aura swap. we only run 1 aura. You can experiment with Eldritch Battery, but I don't think it's worth it.The ES is a nice defensive layer and regens same as health.
Rejuv totem, stone golem - strong life regen for bossing. Won't help much in mapping, but it's another button to click if you're bored.
Vaal/RF - exists to boosts our spell damage. It can finish off most packs. but it's not that high damage. It can stay 4linked in helm, since we have the extra slots.

Shield Charge+Flame Dash for mobility. Tons of extra slots for support gems. Consider a second wind setup, or something with Empower to boost damage.
1 mark/curse setup. Do not need flammability with Inquis node, it gives us all the fire pen we need. Mark any strong mob and they'll die faster. Curses not needed for anything below bosses, they die fast anyways.

Bossing gem swap - Vaal Firestorm/Firestorm. Even with Pinpoint support, it is superior dps, but rolling magma works fine. Pinpoint adds a lot of ST damage and is better for Maven invitations.

This build got a 2x damage buff with new tree and Skin of the Lords. New Life node enabled 15% max life, and we save a point on tree, and provides armour cap with Determ active.
We will potentially get a massive mapping boost if Prismatic Burst is any good. Can probably replace Cruelty or Pinpoint even.

Shotgunning is not enabled in calculator. Rolling Magma does damage, once per WAVE, once per bounce. With slower projectiles, we get 2 bounces per cast, on a boss. Maybe 3 if we're right on top and they're thick.
Max 3 bounces x 2 spell cascade = 6 hits per "cast", this damage increases with Pinpoint. This is of course if you don't want to use Firestorm on ST.
Walk up to boss, refresh totem/golem, activate Vaal RF, drop flame wall x3 on boss, aim cursor at feet. Hold down button until boss dies.
Molthen Shell on left click, vaal RF middle,RM right, Q=shield charge, W=curse, E=flame wall, R=flame dash, T=totem. Ctrl for aura+aura+aura+RF+golem

Map mods to avoid: Cannot regenerate health. This is just too annoying unless you want to run double life flask and speed through it
Content cleared: Atlas, 80% delirium maps, all bosses, all invitations, 100% quant Feared, uber elder/shaper
Not attempted due to being lazy: Uber Sirus/exarch/eater/maven/cortex
Cannot do wave30 simul without mageblood, I capped out at wave26. Bosses get too tanky and our life regen means nothing to them. Totem/golem die instantly and there's so safe spot to hardcast.
This is the issue with Feared as well, it's not deathless, but I did it with 1mil pob dps. If we high-end at 5-7mil Firestorm dps, you can probably nuke them one at a time. 
I was skirting around the edge of room off-screening all 5 bosses at same time.
This build compared to spark, is a lot less intensive and a lot less investment. No one plays it so everything is cheap. It doesn't **** your screen or eyes, and you can facetank 98% of the game's content.