Auto-translated
Yesterday, I completed this mission... I played it for about 9 months (in-game time) and about 6 hours in real life... Oh, it was tedious... Right at the beginning, when I had just taken my first town, the turquoise player showed up. I defeated him in an auto-battle while staying in the town. But when I broke through the garrison and took a second town, he came back again... at the worst possible moment, when I was weakened by the garrison! And I had just started buying Cyclops, while he already had 18 of them.
I abandoned everything, and after several attempts, I finally managed to get on a boat and escape. He followed me, capturing one of my two towns along the way.
We sailed and sailed, he followed me, I fled from him, and then, on the arena, a purple clown appeared with 2 heroes on ships and a 3rd stationary hero in front of the green player's town. The first 2 landed on my shore and just stood there, not moving.
I was no match for either of the purple heroes, just like I wasn't against the turquoise player. I just skipped my turns. Fortunately, the turquoise player stopped chasing me and sailed to the shore where the 2 purple heroes had landed.
Meanwhile, with my second hero (the leader of the black clan), I retook the town that the turquoise player had captured from me earlier. The purple players watched all this and didn't even flinch.
The turquoise player landed and killed the weaker purple hero.
The stronger purple hero killed the turquoise player. After killing him, he just stood there, doing nothing.
After gathering an army from 2 towns, I killed the purple hero on my shore, sailed over, and killed the purple hero on the green player's shore. I took the green town, sailed to the right towards the mentor, re-skilled my hero with the ultimate skills in mind, and then headed towards the remaining town of the turquoise player.
How was it for you? Tell me (if you played on the "Hero" difficulty). I'm curious because my brother says that the turquoise player only came to him once with a weak army, and that the mission is easy and can be completed quickly. He also told me something about dead unicorns and minotaurs lying on the native shore, saying that this is why the purple player couldn't pass, but I didn't see any cutscenes or events with dead unicorns and minotaurs during the game. Maybe I didn't play correctly or didn't kill the enemies in the right order? :)