Armored Core (Japanese: アーマード・コア, Hepburn: Āmādo Koa) is a third-person shooter mecha video game series developed by FromSoftware. The series centers on a silent protagonist who takes on work as a mercenary pilot in the far future, operating large robot combat units known as Armored Cores at the behest of corporate and private clients. As the player completes missions for these clients, they gain credits to improve their Armored Core and unlock further opportunities to make money. Some games include an "Arena" mode in which the player fights other Armored Core pilots in head-to-head battles, which can reward the player with further income or prestige.

Several story continuities exist, spread across 13 main games, seven spin-offs, and three remastered re-releases, with different releases divided by a different set of "generations" of sequels that starts with every numbered entry. The first game in the series, Armored Core, was released in 1997, while the most recent, Armored Core VI: Fires of Rubicon, was released in 2023. The series has been released on various PlayStation and Xbox consoles, as well as Windows and mobile phones. In 2007, the series was adapted to manga by Fujimi Shobo as Armored Core: Tower City Blade, and in 2024, to television by Tim Miller as an episode of Secret Level titled Armored Core: Asset Management, starring the voices of Keanu Reeves, Erin Yvette, Temuera Morrison, Patrick Schwarzenegger, and Steve Blum.

In the original continuity established by 1997's Armored Core through 2001's Armored Core 2: Another Age, Earth experienced a cataclysm known as the "Great Destruction" and humanity has been forced underground. Corporations begin fighting for dominance, leading to the increasing reliance on Armored Core pilots called Ravens. Following the events of 1999's Armored Core: Master of Arena, humanity rebuilds and colonizes Mars. Through 2000's Armored Core 2 and its expansion, Another Age, the fledgling Earth government struggles to maintain power as opportunistic corporations exploit the power gap and rebel groups resist against the hegemony of government and business interests.

The series was rebooted with 2002's Armored Core 3, beginning a new story arc that concluded with Armored Core: Last Raven in 2005. Following a global nuclear war, humanity has retreated underground. Following centuries of rule by an artificial intelligence called The Controller, its decay leads to the destruction of much of humanity's underground network, causing them to look toward the surface for safety. By the end of 2003's Silent Line: Armored Core, humanity has fully returned to the surface of Earth. The final two games of this continuity, 2004's Armored Core: Nexus and 2005's Armored Core: Last Raven involve the end of the existing power dynamic of corporations and Ravens fighting over the surface.

2006's Armored Core 4 rebooted the series yet again. Here, corporations have seized control of Earth governments and are waging war across the surface for dominance. A war waged over the course of the game pollutes the environment, leading to the creation of floating cities in 2008's Armored Core: For Answer. Depending on the player's choices, humanity either barely survives the fallout of For Answer's conflict or is completely eradicated.

The third continuity of the series continued with 2012's Armored Core V. A single corporation has dominance over a contaminated Earth and is being opposed by a resistance faction that seeks to overthrow them, while 2013's Armored Core: Verdict Day details the outbreak of another war 100 years later following an apocalyptic event.

Another continuity has begun with 2023's Armored Core VI: Fires of Rubicon. The game takes place far away from Earth in a human-colonized star system on the planet Rubicon 3. Decades prior to the game's start, a powerful resource called Coral was discovered, leading to significant technological advances, but a disaster called the Fires of Ibis scorched the entire Rubicon system and left it highly contaminated. However, the Coral, thought to have all burned, has begun to reappear, bringing multiple corporations into conflict for control of it which, in turn, has brought the attention of mercenaries. Added into the conflict are the Planetary Closure Administration, an organization tasked with quarantining Rubicon, and the Rubicon Liberation Front, a resistance group who venerate the Coral, wishing to end its exploitation and free the planet.

Within the core games of the franchise, the gameplay is generally focused on the player taking the role of a mech-piloting mercenary, taking on missions for various clients and gaining currency from completing them. Missions can involve multiple objectives and pit the player against computer controlled opponents, some of which pilot mechs as well. Upon completion of a mission, the operating costs of the mech, such as repairs and ammunition, are deducted from the total earnings of the player, as well as compensation for destroying valuable objects within the mission area. Likewise, if the player loses a mission, those same deductions occur from the player's direct balance.