13га
It should be even easier to win with the Undead: since the player has two dwellings in addition to the two castles, which together act as one basic resource increase (even a little more), you can accumulate an army of 5 against 4 and already gain an advantage in troops. I envisioned "Cerberus Island" as a map for a quick game, but with the possibility of winning even with a slower approach.
In my opinion, it's very debatable that it's easier to win with the Undead. It's more predictable and simpler for a player who doesn't want to delve into the intricacies of combat mechanics. While I was trying to prolong the game, I noticed that there are almost no diverse morale/luck boosts on the map. Meanwhile, morale is a very important element in a battle with the Undead. For high-initiative demon units, you can attack two or three times on morale before the Undead's second turn begins. Accordingly, the demon can easily defeat the Undead, even if it is outnumbered three to four times. Plus, there's the possibility of getting the Call of Urgash. Finally, a person plays as the demon, while a machine plays as the opponent, which gives even more chances to win. The difference in the number of armies can reach ten.Again, in my opinion, this map lacks the ability to "infinitely" upgrade the main hero. After capturing the Necropolis castle, there are no more events until the end. If the stream of opponents didn't end with just two Necromancers appearing, it would be better, more dynamic. The player would have a choice to play quickly or prolong the game and level up the hero. Currently, the map is only interesting for a speedrun.