The Midwest Furfest Poison Gas Attack refers to a real-life incident that occurred in December 2014 at the Hyatt Regency O'Hare during one of the world's largest furry conventions. An intentional release of chlorine gas in a stairwell forced thousands of attendees, many in full fursuits, to evacuate into the freezing Illinois night. While the event was a serious safety hazard resulting in 19 hospitalizations, it quickly became a piece of legendary internet lore. Today, the meme is used to reference the bizarre imagery of costumed characters congregating in parking lots under emergency lights, often serving as a 'deep lore' joke within the furry community about survival and the unexpected chaos of convention life.