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Artem, don't make things more complicated :p
The situation was as follows: the Sanctuary was located in the middle, between two Castles, and Kir could reach either of them and return to her starting position. Therefore, to win, it was enough to level up two heroes, each of whom could defeat Kir, and then occupy both Castles simultaneously.
And this is purely a matter of time. After a couple of months of gameplay, 100 Chaos Hydras and 50 Titans would be able to defeat Kir with minimal losses, plus there was a very strong 20th-level Brog and a second set of artifacts, so prolonging the game in this case is simply wasting a huge amount of time.

"Это нам идеально подходит!" [Новосибирск, 2013]
"Красавчик! Если только не читер.." [Киев, 2014]
"Это Вам не шутки - нажрался Dust в маршрутке" [Новокузнецк, 2015]
Сам ты фиш (с) :D