The War (stylized in all caps) is the fourth studio album by South Korean–Chinese boy band Exo. It was released digitally on July 18, 2017 and physically on July 19, 2017 by SM Entertainment under Genie Music's distribution. The album includes a total of nine tracks including the lead single "Ko Ko Bop". The War received the highest number of pre-orders at the time for a K-pop album, with more than 800,000 physical copies. 24 days after being released, it became Exo's fourth consecutive studio album to have sold over a million copies. The album was re-released under the title The War: The Power of Music on September 5, 2017. This was the first Exo release not to feature member Lay, who began an indefinite hiatus shortly before the music video for "Ko Ko Bop" was filmed, and the last album