I wouldnt say ruin, but it definitely makes PvP repetitive. Like in Epic Seven, you basically ALWAYS see some combination of the same 4 characters: Mort, Afternoon Soak Flan, Ruele of Light, and Harsetti. Occasionally one is swapped out for Ambitious Tywin or Blood Blade Karin.
Arena is made up of those first 4 like 80% of the time :<
https://gamefaqs.gamespot.com/a/forum/1/12cbe9db.jpg
https://gamefaqs.gamespot.com/a/forum/7/7c87d26d.jpg
( ^_^)/\(^_^ ) Maya High-Five!