One of my favorite events of the year is participating in the PAX Pokemon League (they set up a gym challenge that operates at the PAX Gaming conventions, recently in september there was an online version). I started out challenging the league for a couple of years, but I've been participating as a gym leader in recent years. I usually run Ice type as my theme. That said! This was the team I used for the most recent league:
Mamoswine
Weavile
Mr. Rime
Alolan Ninetales
Rotom-Freeze &
Cloyster
Worked pretty well I was an Elite 6 member and over the course of 55 battles, I had a... 54.5% win rate so like... not bad considering how bad ice is defensively went 30-25