0 A.D.

0 A.D.: Empires Ascendant is a free, open-source, cross-platform Real Time Strategy game under development by Wildfire Games. It is a historical war and economy game focusing on the years between 500 B.C. and 1 B.C. for the first part, and a planned second part for the years 1 A.D. to 500 A.D. The game is cross-platform, playable on Windows, OS X, Linux, and OpenBSD. The game aims to be entirely free and open-source, using the GPL 2+ license for the game engine and the CC BY-SA for the game art.

0 A.D. originally began as a comprehensive total conversion mod concept for Age of Empires II in June 2001. With limited design capabilities, the team soon turned to trying to create a full independent game based on their ideas. The game has been in development since 2000, with actual work starting in 2003. In November 2008, the developers confirmed that they would soon be releasing the project as open-source. On 10 July 2009, Wildfire Games released source code for 0 A.D. under the GPL 2+, and made the art content available under the CC BY-SA. On 5 September 2013, an Indiegogo crowdfunding campaign was started with a US$160,000 goal. They raised a total of US$33,251, to be used to hire a programmer. The majority of the finances are managed by the Software in the Public Interest organisation.

There is no official release date set for the finished version. But the latest version of the game as of 2016, Alpha 20 Timosthenes, can be found on the official website.

"“0 A.D.” is a time period that never actually existed: In the usual calendar, one goes from 1 B.C. to 1 A.D. and skips zero. This reflects the historical fiction in the game: Who would have won if all the factions were pitted against each other when each of them was at its prime?"
 * Anachronism Stew: Downplayed, but given the 500-year timeframe and how each faction is shown at their peak, this is bound to happen.
 * Ancient Grome: Averted. The game makes a point to highlight how varied and diverse the Greco-Roman factions are, be it the Greek city-states, Hellenistic successors like the Seleucids and Ptolemaic Egypt or Rome itself.
 * Attack Pattern Alpha: Averted. The unit formations are based on actual history and combat strategy, including the famed phalanx.
 * Development Hell: The game has been in the works for over 10 years, and in that time has seen developers and code alike come and go.
 * Doing It for the Art: A major motivation behind the game's development. In more recent years however, the developers have also expressed their hopes of bringing back the Age of Empires school of RTS to a new generation.
 * Elite Mooks: The "champion" units of the various factions, such as Alexander's Hetairoi for the Macedonians.
 * Face Heel Turn: Towers and defensive structures in general can be seized by enemies (and vice versa) provided their units live long enough to complete the process. The only real way to take down said structures is to use siege weapons.
 * Fan Remake: The original idea essentially was to make this for the first Age of Empires, but has since grown far beyond that.
 * Game Mod: 0 A.D. originally started out development as a total conversion mod for Age of Empires II before it was decided to make it a fully independent game instead. The game's open-source code is also stated as being very moddable as well.
 * Genre Throwback: To a degree, given how the game intentionally invokes the Age of Empires style of RTS.
 * Glory Days: Invoked, as each faction is depicted more or less at their respective high points.
 * The Glory That Was Rome: The Romans are shown as they were during their Republican era. The Praetorian Guard for instance don't make an appearance as they only show up after the game's timeframe.
 * Loads and Loads of Characters: In addition to the Greco-Roman cultures, updates have introduced a growing number of playable factions, from Carthage and Gaul to the Mauryans of India.
 * Meaningful Name: Not only are updates named in alphabetical order, but they're also in reference to Antiquity in one way or another. Regarding the name of the game itself:


 * Multinational Team: Much like Four Leaf Studios of Katawa Shoujo fame, the volunteer developers making up Wildfire Games and their various contributors are a meta example of this.
 * In-game, the Hellenistic successors tend to be this, combining Greek and local elements. While Carthage takes this further with diverse armies of foreign mercenaries.
 * Obvious Beta: It's still technically (and officially) in an Alpha state, with a number of bugs and unfinished content. Nonetheless, the game has grown significantly more polished with each update.
 * Shown Their Work: The developers have made a point to not only make the various factions look distinct and historically accurate, but also right down to the unit descriptions; units themselves are named in their respective languages, including Latin and Greek.
 * Sincerest Form of Flattery: The game makes no qualms in incorporating elements of Age of Empires and even Rise of Nations through a national borders mechanic.
 * Spiritual Licensee/Spiritual Successor: To the Age of Empires series.
 * Tactical Rock-Paper-Scissors: Like its inspirations, there's a general rock-paper-scissors dynamic among the unit types.
 * War Elephants: The Persians, Carthaginians and Mauryans can deploy these against their foes.
 * What Could Have Been: According to Word of God, an early concept of what would become 0 A.D. was sent to Ensemble Studios as a proposal for their next game. That plan fell through however, with Ensemble Studios eventually opting to develop Age of Mythology.
 * Worker Unit: Played with. In addition to civilians, any infantry unit can also double as resource gatherers and builders in a pinch.
 * You Are the Translated Foreign Word: Each unit is referred to by their respective languages, albeit with helpful translations on what they're supposed to be.