MalkutX: I agree that Basium never does anything under AI hands, but neither does Hyboream. You really saw it take over a whole continent? Can I have a screenshot or save? And are they really that scary when they do?
Twice, but I don't have saves, unfortunately.
The first time I was Faeryl on a Continents map. I shared a continent with Keelyn, who founded Ashen Veil. She had to die, and so did her cities. I then sailed to the other continent looking for more prey, and found the entire place covered in Hell terrain. It was
awful. Demons were
everywhere. The Bannor, the Malakim, and the Ljosalfar and Basium were all trying to fight him, and they were all losing. His empire was so large that I just started a new game, rather than attempt an intercontinental invasion against a foe that large and advanced.
The second time was as the Sheaim. I was on the same continent this time, but trapped behind an impassible mountain range. After I summoned him, Buboes ate Alexis' entire empire. That gave him a huge area to expand in, and lots of pop to do it with. By the end of the game, the entire world was covered in Hell terrain, and Hyborem was in second place (after me).
In both cases, it was simply a matter of feeding him as many manes as possible, hence my planar gate idea that would give him manes (and Basium angels) at random.