Stamina arcanist build with crafted sets and a vanilla monster mask.

Best race: Dunmer. Orc, Khajiit (slightly less damage), and even Wood Elf will also work.
64 points into stamina.
Food - Braised Rabbit with Spring Vegetables can be used both for parsing on a dummy and in content. Arcanist sustain is very good.
Potions - Essence of Health or Crown Tri-Restoration Potion (stamina regen, magicka regen, health regen).

Opening: 
Cast Deadly Cloak and Inspired Scolarship away from the target, throw Scalding Rune, come closer, cast Barbed Trap, cast Elemental Blockade, activate the ultimate ability Languid Eye, cast Cephaliarch's Flail twice, followed by Exhausting Fatecarver, then Fulminating Rune, twice Cephaliarch's Flail again, and again Exhausting Fatecarver. Then start the rotation.

Rotation: 
The main principle is to stack three Crux's by casting Cephaliarch's Flail (triangles flying around the arcanist) and use Exhausting Fatecarver as much as possible. If you have stacked three Crux's and there are 1-2 seconds left on the DoTs, do not recast them, instead, perform a beam attack first and then recast the DoTs.

DoT's priority:
Inspired Scolarship (if you have zero Crux's, always cast this skill before any other), Elemental Blockade, Fulminating Rune, Barbed Trap, Scalding Rune, Deadly Cloak.
The arcanist does not have a finishing phase, so just maintain the rotation throughout.

P.S. If you have stacked three Crux's and have 158-160 ultimate points, it's better to cast a couple more Cephaliarch's Flail, activate the ultimate  Languid Eye, and then cast a beam.
P.P.S. A good addon for tracking the Crux's number: ArcanistJobGauge