A veritable avalanche of chinchillas, as happens from time to time in the South American Andes. Chinchillas are known for their prolific mating habits, and over time, a dangerous chinchilla buildup can occur in elevated regions. Warming conditions lead to instability, and even minor sounds or vibrations can trigger a catastrophic chinchillanche.
Mark: "Did you hear about Edmund getting killed?"
John: "Oh my God, no! What happened?"
Mark: "He was hiking in South America, and got buried in a motherfucking chinchillanche!"