This was the build I most enjoyed this league.
I dropped the league a couple of weeks back but wanted to come and showcase how strong this mapping build is at bossing.
Between league start & hitting lvl 100 I put about 40div into the build.
Biggest upgrade for the build was getting a Watcher's Eye with Vitality leech on it, because now I could drop my life flask and run a Quicksilver or Jade flask.
You do not need a belt like mine with %life, I just found a decent Stygian belt with an open prefix and slammed a Hunter Exalt onto it.
For bossing I swap in Efficacy support and take the 2 phys/chaos nodes by Shadow start & use a Jade flask.
Otherwise for speed mapping I drop the phys/chaos nodes, a life/evasion node, throw in a Quicksilver flask, and go to Trick Shot.
I end up hitting the whole screen with one cast, so build is great for mechanics like legion, harvest, expedition, and blight.
PoB configs only have enemies poisoned, Steelskin off, and only Haste active (100% uptime due to no mana cost).
You get big damage boosts when bosses have ES, and I can generate 8 wither stacks using Withering Step alone but did not include the stacks in the PoB damage calculation.
Bossing: https://pobb.in/OzVCpatbGeaa
Mapping: https://pobb.in/oL_lNgbjRYY6
All credit goes to Ruetoo who made this build.
His builds are here if you want to look at better versions of Poison PF Exsang.
https://docs.google.com/spreadsheets/d/16plDZm894HdJ-W3MJaxtK322U6U_SNWQ3jZd8T58-N0/edit#gid=0
Edit: for this showcase I dropped the 2 phys/chaos nodes. I cleared The Feared and did 100% of my atlas completion with this build after not enjoying cold DoT as a starter.