Yeah it used to be solely card based. But it appears now it is 100% random. No skill based. No connection based. Card based? Yeah no. I literally won flawless 7th games against people on their 2nd or 3rd win... I have like 1600 matches in D2 and D1 and I haven't seen card based since trials of the 9. Not once was I matched up with someone with the same amount of wins. I think they added flawless pool and figured that was more than enough alone.