Guildie rolls Arsenal Merc, and I believe he's mostly Partisan with maybe 1-2 piece Conq., He was hitting me, (6 pc partisan, Weapon/OH Conq, EWH relics) for 7.2K, and max that match 9.1K.
So.. it may be that either he was hitting people with stacked debuffs, or you weren't.
RNG and imho still way hard compared to my nerfed PT only getting lucky 6K crits but mostly 5-5.5k.