Hey there, that's my first post! Last night I made my first attempt on hc immerseus, we had some problem dealing with swelling corruption here is what appened.
I dont have logs btw I'm trying to be as clear as possible.
Raid: 2 tanks 2 Healers 6 dps
We tried to stack debuff 3/4 for each dps and tanks so first wave of adds should have been of 24. Adds killed and back on boss that at this point had 50/60% hp.
Second wave of adds same thing but when all adds were killed boss had 30% hp and so casted Swelling Corruption on himself again.
As I read on Icy Veins Immerseus guide