Supporting and voting for Arbitration Committee candidates based on the belief that the candidates will damage Wikipedia.[1]
Supporting or voting for inappropriate candidates for Requests for adminship, in the hope that the candidate will harm Wikipedia through bad decisions and poor behavior
Subtly vandalizing articles, in the belief that this will frustrate, discourage, and harm readers, in the hope that they will turn to other websites instead, resulting in Wikipedia becoming first irrelevant, and eventually non-existent
Opposing blocks or other sanctions against editors who frequently make contributing to Wikipedia unpleasant for anyone they disagree with, e.g., by mocking them or insulting them
Bonus points for claiming that their uncollegial behavior is acceptable because it doesn't technically violate the narrowest possible reading of the Wikipedia:No personal attacks policy (e.g., "It's not a personal attack because he only wrote 'That's the stupidest thing I've ever read, and it makes me question your ancestry and upbringing', which is an impersonal description of the speaker's own experience, instead of 'You're stupid', which would have been a personal attack.".