Questions, answers, and resolution of disputes regarding the online rating in HoMM5.

Could you please elaborate on this point? Is it permissible to repeat heroes, and if so, how many games does one ban apply to?

The intention was that after a ban, not just one duel is played, but a series of duels (usually 4 or 5 games), naturally without re-selecting heroes; that is, the heroes used are placed in the same list as the banned ones.

Added 2 minutes later
[/U]There are no reservations in the rules regarding repetitions, but it is clearly stated that 10 heroes are banned.

I disagree with the 10 banned heroes; in my opinion, it harms the variety of pairings.
I believe that in Tournaments, the organizer chooses the number of heroes to ban, and in regular ranked battles, players should agree individually, or perhaps based on the principle of bets:
For example, both players guess a number from 1 to 16, and the arithmetic mean of these numbers will be the number of heroes to ban for the duel.