What's that crown over Splatoon player's nametag?
I've played a bunch of Turf wars this weekend because of the Splatfest, and I usually find players with a strange crown logo on their nickname, like ユーゼン in the screenshot below.
It could be related to the Splatfest, that "fish" looks like the stage on which the Deep Cut trio is dancing in the main square.
What's that, and how can you get it?
It's for winning the 100x/333x battle:
Get a Crown for Winning the 100x/333x Battle.
If you win the 100x/333x Battle, you can get a crown that will be shown above your name during the Splatfest. It is just a sign of winning the 100x/333x Battle and has no special effect.