Nurgle is actually so slept on
I thought i was in for a rough time with this kugath campaign on very hard very hard, but nurgle is actually a lot stronger than i thought. The plagues give massive debuffs to enemies and help a ton, and demonic units such as plaguebarers, beasts of nurgle and soul grinders are hilarious tanky.
Great Unclean Ones are also just bonkers, getting up to 2 bound spells (even 3 for a damage spell). I removed Miao Ying from existance by just casting with them (she was level 38 btw), used blight boils to devestate the rest of their armies and finished the battle by getting back up to nearly full strenght with fleshy abbundance.
The screenshot above is Kugath alone vs 3 full Cathay armies, complete with artillery, Terracota sentinels and Sky junks. Not a single unit lost when the auto resolve was crushing defeat.
I do not have either the champions of Chaos or the Tamurkhan DLCs, so i am doing this with just base game units as well.
There still are massive problems with this campaign, the start is very rough, your economy is terrible and the cycle on your military buildings suck ass. I can definitely understand where people are coming from when they say this might be the hardest campaign in Immortal Empires.