A boy performs a masked dance as he participates in a parade during the National Encounter of Mask festival in Barva de Heredia October 30, 2015. (Photo by Juan Carlos Ulate/Reuters)
A Palestinian woman paints a mural, depicting a masked Palestinian holding a knife, in support of Palestinians committing stabbing attacks against Israelis, in Rafah in the southern Gaza Strip November 3, 2015. (Photo by Ibraheem Abu Mustafa/Reuters)
A Palestinian protester uses a sling shot to throw stones towards Israeli security forces during clashes on the Israeli border Eastern Gaza City, Friday, November 6, 2015. (Photo by Adel Hana/AP Photo)
A woman holds her umbrella while walking against strong winds as Typhoon Soudelor approaches Taiwan in Taipei, August 7, 2015. (Photo by Pichi Chuang/Reuters)
A mahout rides on an elephant in the city of Amritsar, India, 08 November 2015. Such elephants are often accompanied by their caretakers who ask for alms from people in the streets. (Photo by Raminder Pal Singh/EPA)
A girl reacts as she receives polio vaccine drops during a house-to-house vaccination campaign in Yemen's capital Sanaa, November 10, 2015. (Photo by Khaled Abdullah/Reuters)
A member of gay and lesbian organizations puts on a mask during a march in support of the Civil Union project law in Lima, March 7, 2015. REUTERS/Enrique Castro-Mendivil (PERU - Tags: POLITICS SOCIETY)
A man dressed as Ironman takes a seat in the cafeteria on the second day of the London Super Comic Convention at the ExCel centre in east London, on March 15, 2015. (Photo by Justin Tallis/AFP Photo)