How do you get the Season 2020 - Flex Grandmaster Icon?
It was a ranked reward. Riot's description in the client reads: “This icon was earned by finishing Grandmaster in Flex Queue in Season 2020”
Is the Season 2020 - Flex Grandmaster Icon still available?
No. The Season 2020 - Flex Grandmaster Icon was a ranked reward: to get it you had to reach Grandmaster in Flex during Season 10 (2020). Riot does not give out past ranked rewards again, so it cannot be earned anymore.
Season 2020 - Flex Grandmaster Icon is one of the rarest LoL summoner icons.
