“Heroes of Might and Magic V: Tribes of the East”

I think that the "sacrificial altar" is a useless thing for evil factions: Orcs - can sell creatures in the city for money. Necromancers - they use "non-native" creatures better than anyone else, which is why I love necromancers. Demons - the same altar, but in the city. Warlocks - increases the growth rate in the city. And the fact that they give little experience for creatures, means they can be useful.