Ace Combat 2 Final Mission 21

Ace Combat (AC; エースコンバット; Ēsu Konbatto) is a hybrid flight simulation action video game series featuring 18 games published by the Japanese company Namco Bandai Games and produced by Project Aces, an internal development team. The series emphasizes fast-paced action and dramatic plots, and has established itself as one of the most successful arcade flight action franchises.

Most games of the series take place in the same fictionalized world populated with fictional countries with details loosely based on real-life location, events, and wars. One of the main selling points of the series is the ability to pilot a range of aircraft that include accurate or slightly modified representations of present day military aircraft, prototypes that never saw actual battle, and completely fictional boss-type superweapons. Longtime fans of the series are rewarded with small hints of the continuity between the games, as some characters and events are referenced from one game to another.

The first three titles in the series were released on the Sony PlayStation system (Air Combat also known as Ace Combat in Japan, Ace Combat 2 and Ace Combat 3: Electrosphere). Three subsequent titles were released on the PlayStation 2, (Ace Combat 04: Shattered Skies, Ace Combat 5: The Unsung War and Ace Combat Zero: The Belkan War). Two titles were released on the PlayStation Portable system (Ace Combat X: Skies of Deception and Ace Combat: Joint Assault). One title was released on the Xbox 360, Ace Combat 6: Fires of Liberation. Ace Combat Xi: Skies of Incursion was released on the Apple iOS in 2009. Ace Combat: Assault Horizon was later released on both the PlayStation 3 and Xbox 360 systems. Namco Bandai later revealed working on a new Ace Combat title for the Nintendo 3DS, which revealed to be Ace Combat: Assault Horizon Legacy. In 2013, they revealed Ace Combat Infinity, the first free-to-play title in the series, which was released in 2014 exclusive to the PlayStation 3.

In 2011, Namco retconned the Ace Combat series as the opening act of the United Galaxy Space Force series, an effort to combine all of the company's sci-fi game franchises into one long continuity. The other franchises include Galaxian, Ridge Racer, Star Luster, StarBlade, Bounty Hounds, and New Space Order.