The Heroes Round Table

There is a very nice trick how you can regenerate a huge amount of lost units during fights against enemy heroes: Prerequisite: Regeneration ability, Lilims and Breeders (you get some as a reward between town B and C). Split your Lilim into 3 stacks of similar size. Before the end of the fight, try ...

One stats booster is missing on the map - south of fort O (Armorsmith).

I'm unable to attack the town P from my ally. Something similar also happened to me during the undead campaign, maybe this was patched - don't kill your allies.

In order to avoid the mentioned side-quest bug, I skipped towns E & F and it worked fine too. A => B => C => D => G => H => I => 9 (main quest) => E => F => ... Maybe going to 9 directly after D via boat with a secondary hero could be a viable alternative. But I didn't try that. Just as a side n...

I am also unable to capture Ludmillas Town G (Apil-Sin). This is actually a correct game mechanic considering that you can only develop one town to rank 4. And if you previously developed town A to rank 4 (city hall level 4) - it would make sense that you cannot capture another town that has rank 4....