A mass pillow fight in Trafalgar Square in central London on April 5, 2014 on International Pillow Fight Day. (Photo by Jane Scanlan)

An Estonian competitor cheers during the “World Medieval Fighting Championship – the Israeli Challenge” in Rishon Letzion near Tel Aviv January 22, 2015. Israel hosted the tournament on Thursday, which includes 14 competitors from seven different countries – France, Belarus, Denmark, Estonia, Russia, Ukraine and Israel. (Photo by Amir Cohen/Reuters)

People carry bags containing their belongings past a burning residential block, caused by a recent shelling according to locals, on the outskirts of Donetsk, eastern Ukraine February 9, 2015. (Photo by Maxim Shemetov/Reuters)

Andrew Profilli of Australia bleeds from the head during his 93kg bout against Priscus Fogagnolo of Australia during CFC 18 at Luna Park on August 26, 2011 in Sydney, Australia. (Photo by Ryan Pierse/Getty Images)

A reveller takes part in the battle of “Enfarinats”, a flour fight in celebration of the Els Enfarinats festival on December 28, 2015 in Ibi, Spain. Citizens of Ibi annually celebrate the festival with a battle using flour, eggs and firecrackers. (Photo by Pablo Blazquez Dominguez/Getty Images)

People look at the Harmony of the Seas cruise ship leaving the STX shipyard of Saint-Nazaire, western France, for a three-day test offshore, on March 10, 2016. With a capacity of 6.296 passengers and 2.384 crew members, the Harmony of the Seas, built by STX France for the Royal Caribbean International, is the world's largest ship cruise. (Photo by Loic Venance/AFP Photo)

A visitor takes a photograph from the North Star observation capsule onboard the cruise ship Quantum of the Seas which is currently docked at Southampton on October 31, 2014 in Southampton, England. Billed as the world's first smartship, Royal Caribbean's Quantum of the Seas is claimed to be the most high-tech cruise ship in the world, with high tech modifications such as virtual balconies in windowless rooms and features such as the first dodgem ride on water, and a skydiving simulator. The ship will shortly begin its voyage from Southampton, where it docked earlier this week, to New York before relocating to the Caribbean for the 2014-15 season. (Photo by Matt Cardy/Getty Images)

Sailors stand on the deck as the USS New York as it passes the Statue of Liberty during the start of Fleet Week May 25, 2011 in New York City. Fleet week, which has been held in New York City since 1984, celebrates the U.S. Navy and Marines Corps with a week of ship visitations and military demonstrations. Fleet Week concludes on Memorial Day with a military flyover to honor those killed while serving in the military. (Photo by Spencer Platt/Getty Images)