Ideally try other races too. Trolls are generally not an end game city. Something like, what, 70% of games will be dark elves and draconian?
And while it doesn't seem like it, war mammoths are actually very good targets to fight with demon lords - they have a TON of health so the demon Lord can keep stealing from them, but they can't attack the demon Lord, so the first strike means means nothing, and they don't do enough damage to ever risk killing the demon Lord unless it's already badly damaged.
However, I am surprised that auto demon lords do that well against those defenders.
And while it doesn't seem like it, war mammoths are actually very good targets to fight with demon lords - they have a TON of health so the demon Lord can keep stealing from them, but they can't attack the demon Lord, so the first strike means means nothing, and they don't do enough damage to ever risk killing the demon Lord unless it's already badly damaged.
However, I am surprised that auto demon lords do that well against those defenders.