  In the summer of 2021, users on the livestreaming platform Twitch were
targeted by a wave of "hate raids," a form of attack that overwhelms a
streamer's chatroom with hateful messages, often through the use of bots and
automation. Using a mixed-methods approach, we combine a quantitative
measurement of attacks across the platform with interviews of streamers and
third-party bot developers. We present evidence that confirms that some hate
raids were highly-targeted, hate-driven attacks, but we also observe another
mode of hate raid similar to networked harassment and specific forms of
subcultural trolling. We show that the streamers who self-identify as LGBTQ+
and/or Black were disproportionately targeted and that hate raid messages were
most commonly rooted in anti-Black racism and antisemitism. We also document
how these attacks elicited rapid community responses in both bolstering
reactive moderation and developing proactive mitigations for future attacks. We
conclude by discussing how platforms can better prepare for attacks and protect
at-risk communities while considering the division of labor between community
moderators, tool-builders, and platforms.
