This listing is for books two and three from Gary Gibson's Apocalypse trilogy: Survival Game: 9781447242895; Doomsday Game: 9789574364589; This series was originally a duology (Extinction Game & Survival Game), but in 2019, the author self-published a third book, Doomsday Game. Because of this, the print sizes run a bit different as well. Doomsday Game is slightly taller than Survival Game.