Honestly, you learn to play it safe against those crowds anyways and not retread areas you were just at if possible to avoid the invis barrels. Once you get the hang of stutter stepping shots while bloodfury is active, it gets really easy to run Dunc. You can eventually get really good at wrangling crowds, popping Bloodlust, and just mowing down hordes. Fire elementals are cheap and fast meatshields as well, so don't hesitate to rebuild your army while bloodfury and bloodlust are on cooldown.
As an aside, unless Pax Mystica's cooldown is short enough, the first teleport is almost impossible to survive. You can try the safe spot, but then you're not dodging barrels, but you won't be hit by the souls. Jump into the crowd, and you need to be getting hits to register asap or you will die, but you can avoid barrels. It's honestly much safer to use the back way to warp into assur's chamber and work backwards, you have a lot more space to work with.
Pictures later, but you go to the top right corner of the chamber where the loot chest and the third sigil drop guy is (to the left after the fountain surrounded by shish-kebabed rogues), and try to blink to the far right and between the middle and bottom of the screen. If done right, you'll end up right inside the first room in Assur's Chamber, and you can just work backwards
Anyways, how do I gear out for quov tsin? I've made cham boots and zod armor to get phys damage down, but the elemental damage is a pain. Do I just swap the topazes out for the resist gems here? https://tsw.vn.cz/acc/char.php?name=DanmakuZero