We need to nominate a dude to the mod team for the EXPRESS purpose of banning this weirdo's alts. I'm grateful to u/DomitiusofMassilia for popping in every few days, but sadly that's not frequent enough. We need a daily reader who can just hit "ban" when he's browsing comments. It won't solve the problem but it'll alleviate it.
We could also freeze new account creation and open it for select periods, announced with pinned posts. Our growth would be disrupted of course, but it's not like that matters that much.
You could try messaging the admins and seeing if they'd be willing to appoint someone under Dom and Clock, since neither seems to be able to moderate obvious off-topic/spam/troll posts.
https://kotakuinaction2.win/send?user=C
https://scored.co/u/c
This sounds like an admin issue anyways. Someone creating hundreds of sockpuppet accounts is best solved by admins who can view more information, and they're a cross-community problem.