The single "Nightmare" was digitally released on May 18, 2010. A preview for the song was released on May 6, 2010 on Amazon.com, but was removed soon after for unknown reasons. Mixing for the album had been completed in New York City, and "Nightmare" was finally released worldwide on July 27, 2010. It met with mixed to positive reviews from music critics but was well received by the fans. "Nightmare" beat sales projections easily, debuting at number one on the "Billboard" 200 with sales of 163,000 units in its first week. After finishing recording, in December, Portnoy and the band posted simultaneous statements on their websites stating that he would not be their replacement for The Rev. However, Portnoy did travel with the band overseas in December 2010 for three shows in Iraq and Kuwait sponsored by the USO. They played for U.S. Soldiers at Camp Adder, Camp Beuhring, and Balad Air Base. On January 20, 2011, Avenged Sevenfold announced via Facebook that former Confide drummer Arin Ilejay would begin touring with them that year. He was not yet considered a full-time member at this point.