If we were to burn NH4Cr2O7 with HgSCN in the Dark Ages in Europe and show it to anyone, it is us who would be burning next on a fiery cross of Inquisition. And it’s no wonder, since this experiment produces a truly marvelous result. At first, as you ignite the mixture of NH4Cr2O7 and HgSCN, all you can see is that it is slowly burning with a reddish flame. After a while, however, a crater is formed in the middle of the burning pile, and then, suddenly, tentacle-like appendages start sprouting from the burning mixture. And you can almost hear the scream of the mad occultist – “Come forth, Kraken! Come forth!” But of course, this is simply a chemical reaction that is called the "Pharoah's Serpent". It was also often sold in firework stores until people realized that it was toxic.

The world's longest moustache (belonging to one Ram Singh Chauhan of Rajasthan, India) measures a staggering 11.5 feet, or nearly 4 metres.

A boy looks on as fire fighters try to extinguish the fire at oil wells, were set on fire by Daesh terrorists as they fled after Al Qayyarah town's cleansing from Daesh militants as the operation to retake Iraq's Mosul from Daesh continues, in Al Qayyarah Town of Mosul, Nineveh, Iraq on November 02, 2016. (Photo by Yunus Keles/Anadolu Agency/Getty Images)

Pascal Siakam #43 of the Indiana Pacers dunks against Jalen Williams #8 of the Oklahoma City Thunder during the third quarter in Game Six of the 2025 NBA Finals at Gainbridge Fieldhouse on June 19, 2025 in Indianapolis, Indiana. (Photo by Maddie Meyer/Getty Images)

A Spanish recortador jumps over a bull during a show in Cali December 21, 2014. (Photo by Jaime Saldarriaga/Reuters)

Yokozuna-ranked sumo wrestler Hakuho of Mongolia (top) throws Goeido of Japan during their bout on the final day of the 15-day Kyushu Grand Sumo Tournament in Fukuoka on November 26, 2017. Mongolian grand champion Hakuho won the latest sumo tournament on November 25 as Japan's national sport continued to draw media attention after another top wrestler faced a police probe into an alleged assault. He won the 15-day tournament at 13-1 by Saturday with one day remaining as his closest contenders were all defeated at 11-3 before his bout on the day. (Photo by AFP Photo/JIJI Press)

A Fiat 500c is unveiled at the New York International Auto Show April 21, 2011 in New York City. The New York Auto Show is one of the largest auto shows in the country. (Photo by Ramin Talaie/Getty Images)

Afghan women learn how to make a doll at a workshop sponsored by a Malaysian NGO called Mercy that seeks to help local females to empower themselves on April 15, 2010 in Kandahar, Afghanistan. (Photo Majid Saeedi/Getty Images)