Poorly Conceived Attempts At Whimsy That Turned Into Disasters

At a torch relay ceremony leading up to the 2016 Olympics in Rio, Brazil, a rescued female jaguar brought to the event as a mascot lashed out against her handlers. The jaguar escaped from her handlers and immediately attacked a soldier. After tranquilizer darts failed to subdue the animal, a soldier shot the jaguar to keep everyone safe. 

Animal behavior expert João Paulo Castro told BBC Brasil the jaguar probably reacted in such a way because she was stressed out from the noise and crowds. 

In an attempt to break a world record set by the city of Anaheim, CA, the previous year, United Way of Cleveland in Ohio released approximately 1.5 million balloons into the air in 1986. The spectacle was marvelous at first, the entire sky blanketed in rapidly ascending helium balloons, but the beauty quickly faded into disaster as the balloons inevitably returned to ground. Due to rainfall right before the release, winds blew the balloons away from Cleveland, making the release and subsequent drop someone else's problem.

United Way settled several lawsuits as a result of the balloon stunt. One resident in Medina County sued for balloons spooking their prized horse, while another woman sued for the wrongful death of her husband, who drowned in Lake Erie. He most likely would have been found by the Coast Guard if the entire water and sky had not been suddenly covered in balloons. Because balloons are not biodegradable, they were either an ugly addition to the landscape for a long time to come or a big mess to clean up. 

In 2013, a Jägermeister-sponsored pool party in Mexico took a dark turn when organizers poured four buckets of liquid nitrogen into the swimming pool. They had no ill intent; their goal was to create a smoke-on-the-water effect, but organizers didn't consider how that would affect those swimming in the pool. 

The liquid nitrogen reacted with the chlorine, creating a noxious cloud that left many at the party struggling to breathe, let alone swim. Some swimmers were unconscious and began falling under the water, in grave danger of drowning quietly amid all of the chaos. Nine attendants received medical care after the incident, including one man who went into a coma.

In 1974, following an already rowdy and violent series between the Cleveland Indians and Texas Rangers in Arlington, TX, the Indians decided to host a morale-boosting "10-Cent Beer Night" for fans during a home game against the Rangers. In earlier innings, the resulting beer-fueled unruliness was a little risque but mostly goofy - fans streaked across the field and mooned the audience, disrupting gameplay but not causing any major harm. 

Things rapidly went downhill, however, when Leron Lee of the Indians hit a line drive that whacked Rangers pitcher Ferguson Jenkins in the stomach, inciting an aggressive chant: "Hit em' again! Hit em' again! Harder! Harder!" The situation devolved from there, when fans threw chairs, drinks, bottles, pieces of stadium chairs, and even weapons onto the field. Indians players attempted to protect themselves and the Rangers with their bats. 

The violence ended when a riot squad arrived, and the Indians lost to the Rangers by forfeit.