Just got matched up against a 5 stack in Ranked Flex as a solo player in my promos.
My entire team was upset about it because they had the advantage of being an actual team vs all solo players(Im certain we were all solo because I dont see anything on op.gg showing any of us were queued together, unless it doesnt idk.). They probably were in a voicechat which instantly puts my team at a disadvantage, and on top of that they played like they've been playing together for a while.
Here I thought that I was gonna breeze through these promos because and luck out. My fault for thinking so lol.