Build Guide
No generators. No channeling skills. Just Twister. We use a combination of Cindercoat, APoC, Astral Presence, Arcanot, and RCR on gear to regenerate our arcane power. This allows more time for spamming Twisters. It does put more of a constraint on engaging at least 5 or more enemies to sustain your AP at a reasonable level though.
For single target RG, cast twister only once a second or so to keep stacking stricken, and unload on cold + fire phases to deal max damage. Try to contain the RG in a small area. Same goes for elite packs and such if possible - keep them closed in, and stand in occulus ring procs (item on follower).
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About the video:
Not my best rift, but I think it was my best RG spawn and kill of the rifts I attempted. I think this build still has some room to grow with more fishing, better gear, and better skilled play. Considering the FB intra PTR nerf (down from 5000% to 4000%), GR95+ capable.
Keep in mind that you have to keep casting EB and hitting enemies to survive, so keep an eye on your resource and always try to keep a small reserve there for this purpose. I put EB on autocast (numlock or scripting).
Try and stay up close to larger groups to get higher defense from Halo of Arlyse + APD.
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RCR from shoulder roll + topaz in helm + paragon is very important to maintain consistent casting of twister, even if you get down to low enemy count. This should put you at 27% RCR from gear, and then you also have the effect of Cindercoat, helping reduce cost further.
Huge fire damage bonuses from gear here, which is nice.
The build is a little less tanky than a DMO setup, this is why I've opted for Blur in the passives as well.
Illusionist and Safe Passage for some mobility and added defense.
Pain Enhancer is really nice here. It gives us gobs of AS which is useful for burning down the trash and elites if you happen to get a good map with lots of density.
FB6 damage bonus was nerfed on the PTR (intra-PTR) by 25%. This is about minus 1.5GR. To be conservative, will rate 2GR lower than i had before. Now at GR95+.