 After releasing "Imaginaerum" in late 2011, the band began the Imaginaerum Tour in January 2012 with Anette Olzon as a vocalist and Troy Donockley as an unofficial member.On September 28, before a show in Denver, Olzon became ill and was replaced by Elize Ryd and Alissa White-Gluz (vocalists for Amaranthe and The Agonist, respectively).The next day, Olzon gave her final performance with Nightwish in Salt Lake City.