Diablo has clans, but i never saw a valid point for them neither, lol

how can i join a clan?

all you have to do is ask. set up a 1v1 with a member is usually a good way to find out.

Myriad, join my clan "Dirty Old" :) so we can call you Dirty Old Myriad hehehehehe

there used to be a polish based clan [RZKW]

They mainly played the big poland map back before the membership update(when most of them quit cause they didn't wanna pay lol.) They pretty much acted as a clan though. Back then there was a big group of maybe 30-40 players including myself that would play multiple big poland 3v3's through out the day. [RZKW] players would always team together ofc against the indy players.