Three or more deaths in a single incident, or unsanctioned mass destruction of computers qualifies. The perpetrator{,s} (or the following investigation) must have indicated unfriendly AI development concern as their motivation for the act.
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@benjaminIkuta I don't understand your comment. Some event can be "AI doomer terrorism as outlined in the description of my market" and something else at the same time, and the latter has nothing to do with the market.
@benjaminIkuta Terrorism means the strategy that utilizes aggressive violence to terrify your opponents into behaving the way you prefer them to. Killing AI people or destroying their hardware while sending the message would deter others from doing that. The spirit of the market is about the use of this strategy, the description specifies the criteria to avoid ambiguity.