"Fathers and Sons"

What if, for example, the "father" captures 1-2 Necropolises and builds a Veil of Darkness there? It's a rare case, but possible.

Indeed. Thank you, I've made a correction to the rules:
Building a Veil of Darkness in a Necropolis is prohibited.

Artem, reinforcements are here - check the first post.

So, now there are five "fathers" and even six "children," which means we can start this questionable adventure. Captains, you can decide who plays with whom and when.