You should lock user registration until you can add a captcha and a email verification before people can post.

Fujoshis rule!

There already is a captcha during registration and an email verification process afterwards

A just ruler amongst tyrants

i think closing registration form is good for now
sorry to say this but those spams are annoying -_-' when usually i saw random post of forum, now just spam

also can you block those IP for posting not just the ID, like temporary blocking...

i open shounen subforum and saw till 6 pages of those spam and not continue to look for, can we consider it as an attack?, btw if those spam continue, will it affect the MU like DDOS or something? sorry i'm not really know abut computer stuff,, just asking

The IP addresses they use are different every time

A just ruler amongst tyrants