I'm not going to link any specific matches, but I'll just say that I've been on the receiving end of a really bad few games during my provisionals. I've had solid performances both times and I feel like there was nothing more I could have done in those instances. Is there any material that sheds light on how ranked placement works? I've found nothing conclusive during my searches.
Nothing that I've confirmed but I've read that they might make your promotion matches more difficult to prove you deserve to go up to the next division/tier.
Meant promo matches, sorry. Placement matches yes, I've heard you can get quite a variety of players as far as their rank/ELO variation, so that it gets a feel for what rank you belong at after the 10 matches.
The highest you can get is Plat 1 after placements from what I remember.
The more wins out of 10 you get, the better for how high you end up, but it also weighs specific matches depending on ally/enemy ELO I believe. So if you win against high ELO enemies you stand a chance of getting placed higher. If you lose against low ELO players chances are that you will get a lower rank after placements.
