Block new reg from user cp and turn of member list view for guest and awaiting activation. some of this high volume reg are email harvesters all your members are at risk. There are some live visitors that see how your registration works then they program the volume reg bot and swamp you. If you deny new reg, guest, and awaiting activation from user cp, members list, calender, search. that will detour them. Also set a user name character with a different amount say min 3 max 10. If you have htaccess I have a list of IPs that will put a halt to it.
yes you have to promote legitimate users to a group that has access to forum features.
Stopforumspam plugin, goodye spammer plugin, and akismet
Thanks everyone that has posted. I have almost everything you guys have said already turned on. This morning when I woke up I have 64 highly illegal threads made. People trying to sale creditcards or dumps or whatever I don't even know what it is tbh. I just know its no good. I am getting absolutely no spam other than the same thing. Its getting worse as the days go by...
What I've done is create a special custom profile field. If it is answered as Bot, I have it autoban both the username and ip on global.php. Note that Bot is the top answer for it since bots tend to pick the top choice when more than one option exists. It could be done as plugin running off the global_start hook too. I have only had 2 spam threads since I made the modification compared to about 20.
I figured out what happened. When I changed my theme to my new one, The security question plugin didn't work. I just deactivated it and activated it again and its now working, And I have had no spam since than. Thanks you everyone for the help.