Crampus from Netherworld Haunted House with Amber Thompson, spa staff, at Bliss Spa at W Atlanta Downtown hotel on Thursday, October 7, 2014. A self-guided, dark attraction known for its over-the-top special effects, intense make-up, costuming and stunt actors as well as unique monsters, unusual themes and chilling detail, Netherworld Haunted House in Atlanta is taking over the Halloween holiday this season for its 18th season. (Photo by Hyosub Shin/AJC)

A woman takes part in a four-minute flash mob pillow fight at the Old Town Square in Prague, Czech Republic, December 22, 2016. (Photo by David W. Cerny/Reuters)

The Villarrica Volcano is seen at night from Pucon town, Chile, July 12, 2015. Villarrica, located near the popular tourist resort of Pucon, is among the most active volcanoes in South America. (Photo by Cristobal Saavedra/Reuters)

Migrant Haya from Artoz, Syria, shows a picture of her town as she waits to cross the Slovenia-Austria border in Sentilj, Slovenia October 25, 2015. (Photo by Srdjan Zivulovic/Reuters)

A staff interacts with a white lioness in a private zoo called “12 Months” in the town of Demydiv, Ukraine, January 13, 2016. (Photo by Gleb Garanich/Reuters)

Mask dancers take part in a parade during the the International Festival of Masquerade Games “Surva” in the town of Pernik, some 30 km from Sofia, Bulgaria, January 31, 2016. (Photo by Vassil Donev/EPA)

North Korean soldiers wave along the Yalu River, near the North Korean town of Sinuiju, opposite to the Chinese border city of Dandong October 7, 2014. (Photo by Jacky Chen/Reuters)

The Imperial Russian Ballet members wait to perform Tchaikovsky's “Swan Lake” at Arena hall in central Bosnian town of Zenica December 7, 2014. (Photo by Dado Ruvic/Reuters)