How exactly does super strong ghoul strategy work?

[occasionalplayer]

Sapher played it once - lure monsters to your strong city - ghouls with focus magic, heavenly light, guardian and behind city walls. 
I know this has been nerfed since there are no longer rare monsters, or less frequently. But might be interesting with uncommons. How exactly do you do it though?

[Seravy]

The monsters always target the city where (2*distance+unit count) is the lowest, so juggle unit counts until that's true for your intended destination.

[occasionalplayer]

The monsters always target the city where (2*distance+unit count) is the lowest, so juggle unit counts until that's true for your intended destination.

Thanks. So that means to place e.g. huge numbers of skeletons in the cities you don't want to be attacked?

[Seravy]

Yes, pretty much. And/or removing the ghouls from the destination until the monsters are near enough.

[Sapher]

Unit count is twice as important not distance