Now it's all clear, I was just trying to complete the map without the Blade. It took a long time to get the Blade, so I thought you somehow managed to complete it without it.
Added 7 minutes ago
I immediately killed three freed heroes, Kaitlin, with one Wizard, so that I wouldn't have to worry about them in the future, because they get a lot of troops and stats in events. And I didn't let Gunnar leave his spawn point, aggroing him on Kaitlin and then hiding him behind the red gate.
I don't know, maybe this strategy is wrong, and the killed heroes and Gunnar should do something critically important, without which the map cannot be completed. But I'll find out in the process, and it's more interesting to play than to thoroughly explore the map in the editor and prospector.
I think that the Fairies can be defeated with Crystal magic, even without the Blade, although it will be more difficult and will require more mana. But defeating Fafnir without the Blade, as it seemed to me, is impossible, so I took the Blade to Gird on the north.
And the idea of killing the enemy heroes, Kaitlin, is great! I didn't think of that. I think that they can be killed this way, at the beginning, and nothing critical will happen later if you do it at the beginning of the game. It turns out that with this approach, you can get to that southern closed spawn point much earlier and kill Gunnar without an army, if he is still hanging around Kaitlin.
One downside to this approach is that Kaitlin occupies one hero slot, which will slightly interfere when you can have 12-14 heroes moving around in a day, but that's not a big deal.