7.5-15% Weak Spot Damage. Weakspot Kills also ignore Enemy Hit Mass.
Up to 5-20% Strength based on the charge time of your heavy attacks. Stacks 3 times.
1-4% Toughness for every 10% of magazine spent during continuous fire. Stacks 5 times.
7-10% Strength for every 4 Single Target Hits. Lasts 2s and Stacks 5 times.
Your main role for fighting The Twins is to use your stubber to shred the sister's shield and then change your attention to the Brother to start taking away his health. Coordinating with a team member (preferably zealot) to take off the brother's as you are firing away at the sister's shield.
You will need to depend on the rest of your team to keep elites rushing you, because if too much of your focus is redirected to killing them yourself, the twin's shields stop going down. Having a second Ogryn dedicated to taunt and clearing the elites is a good solution.
The larger you can make your toughness pool, the better. You can't gain any corruption while you still have toughness. My Ogryn had 212 toughness with my curios. 3x +16% from blessings, and 3x +5% from perks.
Change to your melee weapon when each fog stage occurs. Your heavy strikes will replenish your toughness bar enough for you to make it to the fan with minimal to no health bar loss if caught out by it.
You will most likely need the majority off the ammo pickups from the crate so make sure your team are aware of that. I used 3 full refills during the fight.
Don't forget to clear all the traps that have been thrown around the arena as they will be what cripples one of your team members if ignored.