The “Island for One” scenario.

I finished this map the day before yesterday. I still don't understand why it's necessary to accumulate such huge armies. By the time the orange faction attacked (and I had to spend about two weeks building up my army, locking the last green hero in a castle), I had around 500 archers, a hundred vampires, and 45 messengers (the rest were in proportion). I didn't build any bone dragons, and I didn't convert the army from other castles into undead either. The first two enemies – the lower left and upper left – were defeated with almost no losses. I lost a large part of my army against the lower right, as the triple-applied blinding effect on the titans also affected other units. There could have been problems with the fourth. However, I replenished my army with a week's worth of undead growth and defeated him. In this battle, I only fought in the castle against one of them; I finished off the rest on ships. In summary, Ravenna was level 24 at the time of the orange attack (I focused on Chaos, Darkness, Summoning, and Logistics – with Navigation being essential, and Education). The two main artifacts were the books of Darkness and Summoning magic (used as needed). The number of days to complete the game seems to be 90 and a bit (definitely less than 100). Oh, yes, version 2.1, "Veteran" difficulty.