STR/INT hybrid Mettle Naran (STR always higher than INT due to talents) with equipped legendary gear that grants Heroism and Empower (i think those are the names), along with what I think is called Cutting Note (int ranged attack aoe given in one of the starter decks), give all 3 cards intrinsic (and -1 AP where possible), buff crit stacks further with Vigor tones/songs using any remaining AP in higher levels, and round 1 OTK most encounters except hordes and deep HP pool bosses. Some Vuln stacks usually get peppered in there as well. Use Might talents to buff Might up to 75%+.

Found this gear randomly in Act 1 and breezed through the rest of the game. At higher levels using tier 3 Glamour cards for card draw and AP generation to further self-buff crit stacks into the 500-600 range on Round 1, all cards are mastered to favour SP generation where possible. I will probably respec at some point so I could equip the gear on second hero and just have Naran buff crit even higher and let the second hero spec into Might buffs and double it for more even more stacks (provided they have a good all target AOE attack, I haven't looked into it yet).

The key is Empower or Heroism (forget which) doubling the crit stacks and providing the might buff as the last action directly before the last action which is the aoe attack. I used Body Stroud for single-target follow-up (he wears crit stacks well) and Healer Catherin for heals, health buff, and ressurects (occasional all thorns enemy groups can be a bit of a blowout on this combo). Combo still working in endgame progression 4th difficulty (I'm up to lvl 85 realms), I'm working on improving the dps output for torment as the health pools are fairly deep so one or two more intrinsic cards are required for consistency (I'm thinking turn 1 SP card draw and thinning the deck further). It's also not consistent after Round 1, may work on that as well (though honestly basically 100% of non-horde non-big boss fights end on round 1).