“Who is stronger?” – Might versus Magic.

I agree with Kill on some points. I suggest holding the tournament in two stages: 1st - group stage, 2 groups - strength and magic separately, we identify the strongest representatives of the factions. In this stage, we use a Swiss system; 3-4 rounds will be enough to identify the 2 strongest in each group (if there are 8 participants). Thus, the less skilled players will be eliminated on their own, unlike in a round-robin tournament. 2nd - playoffs, semi-final and final, respectively. Here, the 2 best representatives of the strength/magic factions will meet; the 1st in the magic group plays against the 2nd in the strength group, and vice versa. Here, it is possible for only mages to reach the final, which will essentially answer the question of who is stronger. We can also hold a match for 3rd place. P.S. For better gameplay, we can slightly increase the number of rounds in the groups or the number of players advancing to the playoffs.

Organize a mini-tournament among those who took 3rd to nth place in the groups, either for the right to advance to the playoffs in addition to those who have already advanced, or simply make two double-elimination brackets after the group tournament (although I don't quite understand how to combine the confrontation here yet)...

This is definitely not necessary; the purpose of the tournament is to identify the strongest players. The last tournament on the league showed that the loser's bracket stage is simply a waste of time. You can play Heroes as much as you want in fun tournaments.