Leviathan
is, imho, hands down the best weapon for a 2H physical+trauma build (ofc with one mastery being soldier). I get the idea behind this weapon (also the constellation Leviathan), its lore being the mighty sea monster so it bears the attributes of Cold Damage.
However, i can’t think of any build that would fit the best for the bonus cold damage it brings, any thoughts?
Could go with a Nightblade second, they have a lot of cold support. Night’s Chill would be giving you resistance reduction, P-burst sustain and defenses, and Shadow Strike + Blitz is insane mobility.
Took me some time to find it, but here it is: [Warder HC/SC viable] Arc Destroyer (139k top crit!). You can see his gear from the youtube link in the guide.
Since the weapon doesn’t convert physical to cold damage, you can use it pretty much in any 2 handed soldier build, even if the %cold damage isn’t used (the skill still uses 80% weap and some flat physical, so it’s useful for trash).
Honestly, if all you want to focus is the cold damage, then you would be probably better using a Bane of the Winter King instead, imo.
But if you really want to use it, I would suggest going either Blademaster or Battlemage, the latter being better I think.
Something like this was my first instinct:
http://grimcalc.com/build/GFyYkE
Battlemage w/ Cadence using Discord Xmuter.
50% Elemental Conversion right there.
Using Iskandra’s Elemental Exchange from Arcanist.
Additionally using Star Pact as well.
Might be a decent stepping stone if you want to really make use of Leviathan.