Level 95 Poisonous Concoction Pathfinder^3.23

Notes

BANDITS & PANTHEON:
The priority is passive skills and improving defenses.
Bandits: Kill all
Major God: Soul of the Bring King
Minor God: Soul of Ralakesh

LEVELING:
Follow the early leveling trees and use the Skills and Items section under 'Poisonous Concoction LEVELING' to gain an idea of how best to outfit your character as you progress through the campaign and into maps. This includes a mix of rare items and extremely cheap uniques (uniques for early leveling isn't necessary).
Leveling in the campaign is pretty straightforward. After killing Hillock, choose between with Galvanic Arrow or Caustic Arrow as your primary damage ability. Use this until you unlock Poisonous Concoction at the end of Act 1. Attempt to match the links up to the guide's recommendation.
There is a major respec early on in the campaign. It's expected to be done no earlier than Act 6, at which point you'll have a maximum of 12 respec points through quests. This respec will cost 10 of them.
As of patch 3.21, Poisonous Concoction suffers a loss of 30% increased AoE from the Ascendancy and now endures rising life charge cost per projectile per attack. Both of these nerfs are circumvented greatly by swapping the traditional Greater Multiple Projectiles support out for another damage support gem until endgame.
If at any point you find yourself shy on attribute requirements, you can always sacrifice a point or two for the +30 strength/intelligence nodes nearby.

UPGRADING:
Here are some strong but expensive upgrades to consider that go beyond the budget of this league start build guide (in no particular order of importance).
1) Reaching maximum quality on all gems that provide some benefit from it
2) Acquiring perfect or near-perfect rolls on all flasks.
3) Leveling and corrupting cheaper gems for a chance at a level 21 gem (priority Poisonous Concoction, Plague Bearer, Grace)
4) Swapping damage support gems for their Awakened gem counterparts
5) Divergent Plague Bearer for added global chaos dot multi
6) Divergent Vaal Haste for increased projectile speed
7) Anomalous Herald of Agony for slightly increased Withered stack application
8) "40% increased Poisonous Conction Damage" helmet enchant (or AoE variant if you want to try dropping Carcass Jack)
9) Squeezing in an Enlighten support and adding an additional aura or Aspect of the Spider
10) Pairing the corrupted implicit on amulet "You can apply an additional curse" (or Whispers of Doom anoint) with "Curse Enemies with Despair on Hit" on gloves.
11) Socketing a massive wheel Thread of Hope near the Ranger starting area for more powerful passive skill point allocation opportunities
12) Adding an Inspired Learning or Brutal Restraint to the Ranger side for more character power
13) Swapping the rare belt for Headhunter or Mageblood

PRICING:
Prices of uniques are subject to fluctuate wildly on account of builds gaining unforseen levels of popularity. In the case of this build, no unique here is an extremely low-tier drop and therefor particularly susceptible to this phenomenon.
For reference, these are the following prices from day 3 of the previous league on softcore trade, courtesy of poe.ninja. Prices will generally be much higher for perfect or near perfect rolls.
Leper's Alms: 5c
Carcass Jack: 5c (not 6-linked)
Asenath's Gentle Touch: 20c
Maligaro's Cruelty: 2c
Circle of Nostalgia: 10c 
Death Rush: 50c
The Overflowing Chalice: 2c
Dying Sun: 30c