XenForo Have you seen..

As with many of our previous releases, XenForo 1.4 is adding more options to help prevent spam from being posted on your forum. Our focus here is mostly directed towards preventing automated bot registrations.

Additional CAPTCHA Types
Out of the box, we now support a number of additional CAPTCHA providers:

Text CAPTCHA -- this is a service that provides Q&A style CAPTCHAs like "Which of 47, sixty two, 18...

Anti-spam Improvements