Aurelion Sol Star Bug
https://cdn.discordapp.com/attachments/221309706717757440/455165781555150859/Desktop_Screenshot_2018.06.09_-_20.09.05.96.png
I was playing on Butcher's Bridge and ended up going against Aurelion. This is the only time recently I have gone against him but through the game he would have 1 star visible, and it wasn't until the game finished his other stars appeared.