I know that blocking certain types of vandalism in the abuse filter will force them to think more and more creatively (and hopefully stop). It's possible they all edit under the same range, as well, which means blocking that range could help, but I don't want to do that the automatic way that abuse filter provides without knowing that it's not going to inadvertently block someone doing something good (and I don't think the page blanking one should have that turned on even if I was confident in it because blanking is a fairly minor offense... I should look into these blocking mechanisms...).
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