Board Thread:General Discussion/@comment-37194541-20190904195001/@comment-366087-20190904205940

Some wikis agree to be Affiliates. Others might call themselves Sister Wikis. Sometimes these agreements between select wikis include a "Three Musketeers"-like reciprocal "Blocked for One, Blocked for All".

Some admins simply watch the activity of a user and if they see them acting TRollish or vandalizing one or a few wikis—especially in Central—they decide to preemptively block them from theirs.

The Rules of some wikis even explain this as the case.

As already mentioned, it's not a rule to be found in ToU, so it is not a violation. After all, Staff allows Wikis to run themselves as they see fit.