Capital Conquest is a multiplayer mode in Ace Combat: Assault Horizon. Similar to Siege Battle from Ace Combat 6: Fires of Liberation, this mode consists of two teams of players, fighting in tandem with AI-controlled friendlies over the control of a capital city.
Each game opens with the factions in play spawning above their respective headquarters, located at the opposite ends of each map, and are given the objective of gaining control over a communications tower located in the middle of the map, which is highly resilient to damage and is defended by team-neutral armed forces, the most important of which are attack helicopters and SAM launchers.
When a team destroys a communication tower and takes it over, all neutral targets are converted into allies and an Air Strike Mode pathway to the enemy HQ is opened, which players must then hit to attack the enemy's HQ. The target is highly resistant to damage, and is protected by large groups of anti-air vehicles and SAM platforms. Pilots can work together to attack the enemy base simultaneously, thus maximizing the damage dealt.
On the left side of the screen, two health bars display the strength of both parties' headquarters. When the health of the player's base reaches 20%, the ability to fly bomber aircraft is unlocked, but only if the communications tower is under their control. Bombers are slow and have limited mobility, although their firepower allows them to deal a severe blow to the enemy's base. If either base's health is depleted, the match will end.
Matches can be set as 4 vs. 4 or 8 vs. 8. At least two people on opposite teams are required in order to begin the match; AI aircraft can fill the remaining slots, or can be disabled altogether, but the AI decide their aircraft.
Capital Conquest can be played on seven maps (five available with the game, two available as DLC). Each map was available as a separate faction on the official Ace Combat website, where players could select their platform and faction for global control. Seasons were periods in time during which factions attempt to gain as much control as possible. Every six weeks, a season ended, a winner is decided out of the available factions, and global control was reset. Players had to then choose a new faction for the new season.
If a map via DLC was added in the middle of a season, players had a certain deadline to change their faction to a DLC faction if they so desired. Otherwise, players could not change factions in the middle of a season.
Once a player had chosen a faction, every point they accumulated in Capital Conquest went toward their faction control over the map they played over. For example, if a PS3 player sided with Washington, D.C. and went into Capital Conquest over Miami, the points the player received went towards Washington's control of Miami. Players were not restricted in their choices of factions whether they downloaded the DLC or not; for example, a player could have joined the Honolulu faction without downloading the map for it. However, they were not be able to contribute to Honolulu's control of Honolulu or Tokyo as a consequence.
In November 2012, the Capital Conquest faction competition (along with stat tracking) was discontinued after running for nine seasons. The results of the nine seasons are still available, but no more seasons are going to run.
In order to accomplish a mission's objectives, players can choose between four types of aircraft, each with different strengths and weaknesses. A cooperative mix of aircraft can complete a match in very short order.
- Fighters are high-speed aircraft specialized in engaging airborne threats, and are able to enter Dogfight Mode (DFM) to pursue enemy targets. They can engage any air targets, but are weak in air-to-ground combat.
- Attackers are aircraft designed to, as their name suggests, attack ground targets. They have strong armor, but are weak against fighters. They can use Air Strike Mode (ASM) to follow a flight route in which they can start an attack run, but only when the transmission base has been secured for them.
- Multiroles are aircraft made for both the role of a Fighter and the role of an Attacker, able to take on targets of any type. They can use both DFM and ASM to their advantage.
- Helicopters are small aircraft designed to attack infantry and ground enemies. They cannot engage in Close Range Assault, but are unique in that they can literally fly under the radar; that is, they can remain hidden from radar by flying nap-of-the-earth. However, they are the game mode's weakest aircraft. Helicopters are quite useful to protect HQ's.
- Bombers are large, slow aircraft with the same design goal as Attackers; however, they are completely defenseless against fighters, except for countermeasures to avoid missile fire. As a trade-off, they can also start a bombing run in ASM, in which they can cause heavy damage to ground forces.