Advance Wars: Days of Ruin, released as Advance Wars: Dark Conflict in Europe and Australia, is a turn-based strategy video game for the Nintendo DS handheld game console. It is the fourth installment in the Advance Wars series (preceded by Advance Wars: Dual Strike) and was released in North America on January 21, 2008; in Europe on January 25, 2008; and in Australia on February 21, 2008. A Japanese release was announced under the title of Famicom Wars DS: Ushinawareta Hikari,[a] but was canceled after several delays. However, on October 30, 2013, it became available in Japan through Club Nintendo as a downloadable platinum status reward for the Nintendo 3DS system.
Advance Wars: Days of Ruin was intended to have a darker atmosphere and more serious tone in contrast to the previous installments in the series, and features a new storyline independent of the previous games. Set amidst a post-apocalyptic world, the story focuses on the Rubinelle 12th Battalion, one of the surviving remnants of the military of the country of Rubinelle, which had been locked in a century-long war with its rival, Lazuria, prior to a devastating global meteor shower. In the aftermath, the Battalion devotes itself to saving any other survivors of the disaster, despite the shattered nations renewing their war against each other and an incurable disease ravaging both sides. Meanwhile, a mysterious faction with unknown motives takes advantage of the destruction and pushes both sides deeper into conflict from behind the scenes.
The objective in Days of Ruin is for the player to use their military force to defeat the enemy's force. Except for certain single player missions with special objectives, there are two ways to defeat an opponent: destroy all of the enemy's units or capture their headquarters. The battle system is turn-based. Two to four forces, each headed by a commanding officer (CO), take turns building and commanding units on grid-based maps. Every turn, units, which consist of ground, sea and air units, can move across the different types of terrain and attack enemy units or perform other actions, such as submerging a submarine or resupplying friendly units. Many factors can affect the battle, such as Fog of War, a phenomenon that prevents players from seeing enemy units other than those in the visual range of their units; various weather conditions; and CO powers.