It looks like we have been targeted by spammers who are busy creating spam pages. This has happened to us before but never as severely as this time. If we are unable to combat the spam, we would try to enable extensions to help us but it is likely that they will not work as we want. We have also contacted Miraheze's Counter Vandalism Team but I doubt they will be able to help us because unfortunately, even IP blocking the accounts has not prevented them from creating accounts again. The spammers have succeeded to get past Miraheze's global abuse filters which protected us the last time there was this type of high amount of spam. We may have to close the wiki temporarily to make it read-only. Thank you.
He has deleted some of the spam pages and globally (across all Miraheze wikis) locked the accounts! We are trying to find a permanent solution at the moment.
After a few hours of trying to combat spam, we believe that we have finally safeguarded the wiki. It has been protected for a day to prevent further attacks. All users will be unable to do anything without editing pages during this time. This is a temporary measure and we have contacted Miraheze's Stewards to investigate this issue. Thank you.
A steward investigated and found that a few major proxy providers had some unblocked IPs. All the IP ranges have since been blocked. This is why the spammers were able to create accounts again even after I blocked them.