AC customization has been changed from the previous Armored Core title, with a new interface and many new parts not found in Armored Core 4. Online mode returns with a new co-operative mode alongside the player versus mode. Gameplay enhancements included a power increase for both Quick Boost and Over Boost, as well as an auxiliary high speed booster known as Vanguard Over Booster (VOB). Another new feature in the game is the Assault Armor attack that becomes available by equipping certain OB parts. This attack uses up all available Primal Armor that the AC has and generates a huge blast consisting of Kojima (highly reactive particles) that destroys or damages all objects surrounding the AC. However, this also leaves the AC vulnerable because not only will the AC lose its PA, it will also not regenerate for a few seconds. Laser blades are deadlier because of the revamped laser blade attack. Once the blade has acquired a lock-on, the AC will instantly rush to the target, traveling a great distance to use the laser blade. All parts carried over from the previous game have had their parameters altered, much like the transition between previous series installments Silent Line and Nexus. The on-screen HUD can now be changed to any of 20 colors. There are now 442 FRS tuning points available to unlock, which is an increase from the 300 (PS3) and 337 (Xbox 360) FRS points available in AC4. Maps are much larger and more detailed including environment damage such as collapsing buildings. The game is also the second in the series (after Last Raven) to feature multiple endings, with three different possible plot branches available depending on your actions and decisions in the game.
Armored Core: For Answer received generally mixed reviews. The scores tended to be about the same or a little lower than those for Armored Core 4. (with exceptions, such as IGN, who scored the game considerably higher than AC4) One of the most consistent complaints among reviewers seemed to be the lack of any sort of online community. Kevin Van Ord of GameSpot stated in his review that there were "fewer than a dozen [players on] Xbox Live" when he tried to playtest the game, and that similar attempts to find a game on PlayStation Network yielded "just a single opponent".