Question for Constellations

It says that you can earn an extra ranked mark for achieving “Rising Star” when you win a game. And that you can get Galio’s Aegis on a loss. I’ve apparently got Rising Star twice, giving me 2 extra marks. But i have absolutely no clue how i did it. Anyone have an idea? And i’m just gonna assume Galio’s will happen if you get an S on a loss.