The CSR on Flood appears to be based on your placementin the game compared to other players and their ranks. You rank up if you beat someone above you and you rank down if you are beaten by someone below you.
As for the scoring, Flood get no special bonuses other than Final Conversion, while Humans get Last Man Standing and Clever bonuses.
Hope this helps! I’m an avid Flood fan, and there’s a lot of enjoyment hidden within this gametype. So go! Explore and enjoy the crud out of it!
Despite my massive leveling, I don’t know EXACTLY what ranks you, but it says that ranking is based solely on score in comparison to others.
Survival Time doesn’t benefit you.
Kills/medals are the only way you can score.
The way you rank up is to score consistently higher than players who are ranked higher than yourself. If you for say beat me 10 times, your rank would benefit and increase for an unspecified amount of levels, while I rank down. On the opposite end, if I win and I am higher ranked, then I won’t receive any benefits because the system EXPECTS me to win.
EDIT: Beaten! Nooooo!
I would listen to Cizlin, he is better than me. But anyways, just rank consistently higher than better ranked people.