First I would like to clarify that like half a year ago I made thread in this forum regarding how to gear up bowa and I became friend with mhlg so our bowas are similar but still they differs in few details.
My first advice to anyone who is thinking about bowa: dont be shy to put 0points into vitality !

I have made 3builds so far.
1) Bowa shooting with Mist - 80light res
- highlord amulet (IAS, DS + light resists)
- maavina Belt (mana leech + FRW)
2) Bowa shooting with Windforce - dmg build, easiest 95IAS, easiest mana and life leech, bad resists, worst AR (but still high enough)
- Atma (dmg)
- Razortail Belt (100% Pierce + dmg)
3) Bowa using Faith - 3 auras, maxed fire and light res, dmg bit lower than with Windforce (I dont have perfect roll), 82% Pierce - currently using
- highlord amulet (IAS)
- nosferatu Belt (IAS)
GEAR:
1) & 2)
Andariel Visage socket with +15IAS
Fortitude
Laying of Hands
Raven Frost
2nd ring is rare ring with AR, dmg, +dex/str, all res, mana (sadly in my ring mana leech was missing)
Gore Rider
off hand Harmony for FRW
merc is Act 1 with Faith
3)
different Helm: I decided 3os Tiara with 87life instead of with 12max dmg
rare ring with mana leech (currently I run with 2% mana leech and its really enough to clear everything, but u have to check ur mana and switch between magic and Guided Arrow - both cost 0mana - multishot and Strafe. I recommend 4+ mana leech)
merc is Act 2 with Pride.
All builds are quite expensive because they all need Faith bow with 13+ Fanaticism. And the most expensive part are small charms and jewels. But the least expensive I find Windforce which is pure dmg, dont expect anything else than dmg, it doesnt have anything else, but damage it provides a lot ! But what I hate about this build is when ur merc dies or is lost somewhere on map you lose Fanaticism and your attacks per seconds drops from 3,57 to 2,77 so u lower ur dmg by 30%. So thats the main reason why I prefer build no.: 3.
And now to Atma scarab amulet.
With Windforce its epic, maybe its just my feeling or it comes to multishot vs Strafe. I dunno but I prefer to use Magic Arrow vs immunes over Strafe.
Problem with Strafe (vs multishot) is that Strafe shoots on all targets, so even the overall dmg is higher it takes more time to kill enemies. So when I run against immunes. I prefer to focus fire. And because Strafe shoots everywhere it procs its amplify dmg on all monsters than you want and if it procs on right target, then next Arrows will hit other monsters.
Atma scarab is epic vs bosses. Sometimes if I am lucky and game calculate max possible dmg + amp procs I am able to make diablo health dissappear with few guided Arrows.
I have tried to skip maxing Magic Arrow to save skill points for passive skill tree, but I never felt comfortable with Atma amulet (well I dont run Arcane Sanctuary). And when there are those annoying lighting ghosts which killed all of us many times

Atma is really great (you cant forget 75% poison res), it increases dmg quite a lot, but to use Strafe and rely on Atma proc seems to me like very bad decision. Because magic Arrows can proc and benefit from amp dmg too!
The Flash
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