From this moment on, you are a Raven.
It is a new world order, where lives are bought and sold in a twisted free market economy. But there are always exceptions to every rule…
— North American manual
A third-person action Mecha Game released by FromSoftware in 1997 for the original PlayStation, and the first installment in the eponymous series.
Following a cataclysmic war known as the Great Destruction, the surface of Earth has become uninhabitable. Mankind has found shelter underground and the world's governments have made way for ruthless corporations, who wage war on each other through overt and proxy means. Existing outside the corporate system are Ravens, independent mercenaries who take on the corporation's dirty contracts through the mercenary mediating and arbitration organization Raven's Nest. Piloting modular mechs called Armored Cores (ACs), the Raven's only loyalty is to the highest bidder.
As a newly-inducted Raven into the Raven's Nest, you are well positioned to take advantage of the increasing hostilities between the reigning corps Chrome and Murakumo Millenium.
The game is followed by the sequel slash expansion packs Armored Core: Project Phantasma and Armored Core: Master of Arena on the same console and Armored Core 2 on the Playstation 2. As part of a Milestone Celebration, original Concept Art, music, and remade missions are included on the bonus "Revolution" disc for Armored Core: Nexus. The game would prove to be a remarkably solid template for the rest of the series, with none of the sequels until 2007's Armored Core 4 making many fundamental changes to the core gameplay and game structure.
The game provides examples of:
- The Ace: Top ranker Nine Ball gives off this impression, having a menacing red paint scheme, a perfect mission record and being described as the guy trusted to handle the tough jobs. Of course, it turns out he's actually the physical avatar for the AI controlling the Raven's Nest.
- All for Nothing: Regardless if you side with Chrome or Murakumo Millenium, both factions will collapse shortly after a major victory on the other.
- All There in the Manual: Japan-exclusive guidebooks go in much greater information about the setting and give faces to the other AC pilots.
- Covers Always Lie: The western cover depicts an AC dual-wielding assault rifles despite that left-hand rifles and machine guns don't appear until Armored Core: Silent Line, the seventh game in the series.
- Crapsack World: The world of Armored Core is not a nice place to live in, what's with the unchecked corporate wars that often deliberately target civilian assets, rampaging bio-weapons and unethical corporate experiments. The story introduction in the English pulls no punches in describing how bad things are for the average Joe.— ''Though the world is making a rapid recovery through ruthless corporate competition, social disorder resurfaces as disparities in wealth, terrorist outbreaks and racism refuse to go away. The ruling Corporations, seeking ever-greater power and wealth, refuse to let the strife end.
- Cybernetics Eat Your Soul: Human PLUS, experimental surgery using pre-Great Destruction technology, installs cybernetic implants that increase one's abilities but it is also shown to drive more than a few test subjects insane. The mission "Destroy Plus Escapee" has you put down one such fellow, who's said to have become deranged beyond rehabilitation.
- Subverted in the case of the Escapee. With his dying words, he tries to warn you of the truth of Human Plus, and it turns out that he wasn't deranged but merely had broken from the Raven's Nest AI's control, with you being sent in to eliminate him before he could do significant damage to the AI's plans.
- Disc-One Nuke: The WG-1-KARASAWA can be obtained early-on during the "Destroy Fuel Depot" mission, this energy rifle boasts high damage (which can be further increased with optional parts) capable of destroying most enemies in one or two shots, along with an ammo cost of zero, making it a great crutch for beginners. However the small locking area and low ammo count might discourage its use on later missions.
- Early-Bird Boss: During the "Attack Urban Center" mission, the player will encounter the rank #2 Raven Valkyrie. Her AC is extremely powerful and can easily destroy a new player's AC with a slug gun barrage. While she can be defeated in this mission, it's easier to hide and evade her during the last minute to avoid the extra ammo and repair costs or outright failing the mission.
- Early-Installment Weirdness: Not as much as you might expect. Despite being the first entry in a now long running franchise, the game's atmosphere and gameplay firmly establish the foundation that the rest of the series would generally only expand on in increments. The most significant point of difference is the lack of an Arena (although some future entries wouldn't have one either), as well as the poor weapon balancing and unusually unforgiving debt system.
- Evil vs. Evil: Neither Chrome nor Murakumo Millenium are particularly sympathetic, and the player isn't expected to align morally with one or the other regardless of their route of choice. It might be a case of Evil Vs Oblivion, as Murakumo Millenium's goal in the game is to re-activate the Kill Sat Justice; it's unclear what their motivation for doing this is, but it's hard to imagine it'd lead to anything but absolute catastrophe.
- Great Offscreen War: The nature of the Great Destruction and who fought it is not elaborated upon in-game, though some missions involve assists in the securing of pre-war military assets. External materials go into further detail; escalating economical crises, environmental destruction and food shortages led to global riots, which leading nations tried to resolve in one swift blow using the Kill Sat "Justice"; predictably, not only did this fail to quell the unrest, it further destroyed the environment, leading to rising sea levels and years-long tropical fires which made the surface world borderline uninhabitable. With the concept of "countries" itself now all but demolished, what remained of humanity retreated underground to relative safety.
- Harmless Enemy: The mission "Worker Robot Removal" tasks you with destroying tiny, barely-mobile robots who can't harm you in any way. The challenge is dealing with them without having a stray round or accidental blade swing hit one the active generators around the place and incurring a monstrous bill from the damage done to your AC.
- It's a Wonderful Failure: Failing any mission past the fall of Chrome and Murakumo results in a FMV cutscene showing records of your existence being deleted from the Raven's Nest database.
- Master Computer: At the very end, it's revealed that behind the Raven's Nest is a computer core, implied to have been left as some sort of security net to keep society and the corporation's war stagnant and prevent an event like the Great Destruction from happening again. Its destruction brings about the end of the "Age of Rebirth", though as Armored Core 2 shows, humanity carried on fine regardless.
- Mercy Mode: If the player incurs too much credit debt (50K), a cutscene shows the player character selling their body to science, undergoing experimental "Human Plus" surgery and restarting the game with your debts cleared, your existing inventory and a new ability. The process can be undertaken multiple times, giving increasingly useful augmentations like having a built-in radar, doubled energy, being able to fire energy waves from laser swords, and getting the ability to fire heavy shoulder-mounted weapons from bipedal legs without kneeling.
- Mirror Match: Every enemy AC fought in the game uses parts that are also available to the player, meaning that the player can create and pilot a mech with the exact same build as them, even against them.
- Obfuscating Stupidity: For the mission "Destroy Base Computer", the briefing is written in thickly-accented English and details in a rambling, confused manner the Raven's inability to destroy the defense system of a base. It's all a ruse, once you get there it becomes obvious the mission is a trap and Boss Savage wants to kill you.
- Red Herring: The final mission is officially named "Destroy floating mines". The mines are easily the least important part of the mission. Subverted in Japanese, where the mission's name is simply "Raven's Nest", though its description still doesn't fully reveal its true nature.
- Rewarding Vandalism: Some missions reward with extra cash you for going out of your way to destroy non-critical enemies and infrastructure. In particular, "Attack Urban Center" gives you extra $$$ for every monorail, car, guard mech and even signpost you destroyed. Even some hidden items (often among the most powerful in the game) are hidden behind non-critical or even friendly targets.
- Skippable Boss: There's nothing actually forcing the player to destroy either Nine Balls in the final mission before destroying the core (although it does counts towards the 100% completion requirements), though getting past it in the narrow corridor can be difficult.
- Shoot the Dangerous Minion: Late in the game, your employers will start getting uneasy at just how much you've achieved and send you off on a fake mission to try and ambush and kill you.
- Shoot the Television: In the ending for the Murakumo Path, a disgruntled man throws a pipe at a TV after watching a new reports describing emerging competition between Murakumo and the up-and-coming Verge corporation, having realized that Chrome's uprising has been for nothing.
- Story Branching: Depending on whether the player picks the mission "Secret Factory Recon" or "Guard Factory Entrance", the player will be locked into two story branches in support of Chrome or Murakumo for the mid to late game. The story eventually converges in the final act as both companies end up annihilated regardless, though the circumstances leading up to it are different.
