"What had been a Quidditch match turned swiftly into a human versus tree battle, which the wizards won only after seven hours’ hard fighting. Nenad was not prosecuted as he had been killed early on by a particularly violent spruce." (QWC)
The Attack of the Killer Forest, which took place at the final of the Quidditch World Cup in 1809, is considered to be one of the worst exhibitions of unsportsmanlike conduct in wizarding history (QWC).
The match between Romania and New Spain (now Mexico) ended in a massive attack by the forest near to the stadium. Located on the edge of the West Siberian Plain, the forest injured or killed wizards in their path. The trees had been bewitched by local Dark Wizards in the pay of Niko Nenad, a hot-headed Romanian player who was known for violent outbursts, including attempts to strangle referees. The battle lasted for seven hours (QWC).
"Attack of the Killer xxxx" as a film or programme title can sometimes be used as a funny or stereotypical reference (TV Tropes or Hollywood Reporter), however this event in the wizarding world was both deadly and serious.
Lexicon timeline of Quidditch
Lexicon list of World Quidditch teams
From the Web
Writing by J K Rowling on WizardingWorld.com (Pottermore): The Daily Prophet
Screenshots of the Daily Prophet coverage of the 2014 Quidditch World Cup (originally from Pottermore), written by J.K. Rowling, and saved on Imgur:
Harry Potter Wiki: Attack of the Killer Forest