A shadow ban works only on the account you use, the spammer who has 35 accounts in his bot is unlikely to read the forum from any one of those accounts. Unless you mean their current bots won't get a banned-error and doesn't realize it needs to switch to the next batch of accounts > that would work!
Yeah that's what I mean. They probably wouldn't notice for at least a while, and any way to inconvenience them would be great.
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