How the fuck do I fight late game Chaos Dwarfs?

So, I'm playing as Eltharion, got the recruit defeated legendary lords mod. Anyway. Teclis and Eltharion's armies just got deleted by one chaos dwarf army. They had lightning strike but I'm not really sure it would've mattered. They cast some spell that took 95% of Eltharion's health out in about 8 seconds. Teclis's army was almost all Sisters and Eltharions was mistwalkers, but the artillery just took out my forces. And blunderbusses and fireglaives mopped up the rest.

I feel like there's gotta be a better solution than (canonical, aka zerg) skaven tactics. But that's all I can think of. I can't even get my forces close enough to do any meaningful damage before all the spells and nukes and whatnot wipe them out.