>>42187149
probably the Twilight Theory civil war, it's a 5-way civil war where you start surrounded on all sides and outnumbered 4-1, but if you push to natural barriers like mountains and the sea you can shore up your frontlines and if you do enough encirclements you can whittle away at your enemy's numbers advantage
Celestial Resistance is also fun because you're fighting a massive civil war inside of another civil war, except you and your enemies are all stuck in a jungle hellhole with no supply, no factories and no ponypower, and you have to outmaneuver them all to win, plus you get tons of cool and fun events about Daring Do and her friends throughout the campaign
Schizo Longsword is also cool because you start off as a single province and have to constantly fight underdog wars against powers a billion times bigger and stronger than you, until you've unified the entire continent