The Alliance Combat System (abbreviated ACS) allows for friends and alliance members to temporarily combine their fleets to attack or defend a target that either might not have been able to attack or defend alone. An Alliance Depot is not required to attack or defend a planet. OGame currently only has this feature implemented in Universes 1 GR, 5 and 18+. All universes starting after 18 WILL have the ACS enabled. It has not been decided whether or not the remaining universes will have the ACS switched on at a later date. (The redesign universes (U42, Andromeda/U44/ Barym/U45 & Electra) all have ACS, except for the newly opened universe Fornax.)

ACS AttackEdit

In order to perform an ACS attack, one player has to perform a normal attack to the coordinates you want the ACS attack to go to. Once that player has told that attack to start, they must click the formation button. From there you are asked to invite players to ACS with you. You can name the ACS attack to something easy to remember. (which is very nice if you are going to do multiple ACS attacks at once) Then you put in players names that you want to invite to join your ACS. The game will send them a message inviting them to join the attack.

After they receive a message, they may select how many of each ship they wish to send in the fleet screen. When asking where to send the fleet, the player selects the name of the ACS Attack from the combat units quick link. When asking what type of mission to do, select the ACS attack and proceed with the attack. (A notable special case is the safety probe).

Redesign ACS Attack DifferencesEdit

The redesign universes (U42, Andromeda/U44/ Barym/Draco/U45/Mizar/Electra & Jupiter) change the way in which ACS attacks operate. First, all players wishing to enact an ACS attack must have each other on their buddy lists. Additonally, there is a change with the redesigned fleet menu. Within the new menu there is a 3-step process. In the first step, you select your ships. In the second step, you select your starting location, destination, and deuterium usage percentage. In the third, you select your mission type & assign resources for the fleet to carry. Under the old system, one would receive an invitation, begin setting up a normal attack (timed correctly within 30%), and select their mission type from a drop-down menu in the 2nd screen. In the new system there is an added two-step process: You must select a combat group from a drop-down menu in the 2nd fleet step, followed by an ACS mission select in the 3rd screen

Using ACS Attack to evade The NinjaEdit

You can use ACS to slow down your attack for a few seconds in order to spy your target just before impact and see if there are any additional fleets on the planet you are attacking. To do this you first invite yourself to an ACS attack to be ready. Then you send probes to arrive a few seconds after your attack (mission type: espionage). The best way to do this is by sending probes at 10% speed so you would have time to do it again if you somehow fail. After that see the arrival time of the probes you just sent and remember it. Then send one probe in ACS attack with your main attacking fleet but to arrive about 10 seconds after the espionage. By doing this you slowed down your attack and gave yourself about 10 seconds to see your new spy report and callback your attack if there are any additional fleets on your target. Note that your espionage probes are coming after original attack should come so if ninja is prepared you will certainly see it.


That means that you deploy your fleet to the orbit of another player's planet (you have to choose the "hold" order for that). You can only deploy your fleet to members of your alliance or to people from your buddy list, and you can't deploy the fleet to people who are in vacation-mode.

To deploy your fleet to another persons planet you choose the "hold" order and set the time how long the fleet should stay there. The longer it stays, the more deuterium is needed. The deuterium is automatically loaded onto your fleet. Remember that you need a high enough cargo-capacity to transport the extra deuterium.


Ship Fuel Consumption/hour
Small Cargo Ship 5
Large Cargo Ship 5
Light Fighter 2
Heavy Fighter 7
Cruiser 30

Battle Ship

Destroyer 100
Death Star 0.1
Bomber 100
Recycler 30
Espionage Probe 0.1
Colony Ship


 BattleCruiser          25


  • Once you recall the fleet, all deuterium is gone.
  • A maximum of five players can hold their fleets on another person's planet.
  • If the planet gets attacked, only the planet owner sees the attacking fleet at his overview screen.
  • If you attack a planet where one of your fleets is deployed, you fight against your own ships.
  • When a planet with an ACS defence is being probed, the number of ACS ships will be added to the planet's original fleet.


ExpeditionColonizationHarvest / RecycleTransportDeploymentEspionageACS DefendAttackACS AttackMoon Destruction

You cannot ACS defend someone who you couldn't attack if they were your enemy; in other words, if they show up as having newb protection, then you cannot ACS defend them.  This means high level players cannot ACS defend low level players in their alliance.
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