Counter-heroes in duel mode (3.1).

...as for the rating of 4-5 thousand, read my previous post and add to that the fact that the UBI rating is not an indicator.
I will play as Ossir against any player in a duel for rating.

I agree, there are examples, I don't remember the exact account names, something like Tom's_Highway, gimlimany, Arantox. All these opponents have a rating on UBI that exceeds 6000, and yet one only played as Deleb in 1.5, the second only played with two Dwarves and Nimue in 3.0, and the third plays with his own super presets. I note that they are all of foreign origin. My opinion is that if a person doesn't shy away from random matches, then his rating should not be higher than four or five thousand, with one exception - DOMOVOY, there's nothing to say here, he's a unique player.
Regarding playing against anyone for rating, there are reasons why it's not possible. Just let me know your UBI accounts so there are no inaccuracies)

The most realistic way to defeat Ossir is with Jalib, this pair is very sensitive to the skill level of the players, but even here, Ossir has a huge advantage, even in the Abyss. Next is Vitya, this pair is also very sensitive, I remember even defeating a Dexosian Ossir with Vitya, but that was in the memorable 3.0, and also in 2.1)