How do you get the Season 2024 - Split 3 Icon?
It was a ranked reward. Riot's description in the client reads: “This icon was earned by winning ranked games in Season 2024 - Split 3.”
Is the Season 2024 - Split 3 Icon still available?
No. The Season 2024 - Split 3 Icon was a ranked reward. To earn it, you had to peak the required rank during Season 14 (2024). Riot does not hand out past ranked rewards again, so you cannot earn this icon anymore.
