Invasion
Whenever a player has a fleet in the orbit of an enemy planet, and if that fleet contains at least 1 invasion ship and soldiers, he may invade the enemy planet. An Army Barracks is required to begin Training Soldiers
Space combat
If there is an enemy fleet, you encounter a space combat before being able to invade. The invasion ship has very poor armour and fleet drive, and with all the expensive soldiers in the fleet it's very important that you provide enough Military Ships cover for this ship.
If you still have invasion ship after combat occurs, you can invade the planet even if there are enemy military ships in its orbit.
Invading
The invasion ship can carry 40,000 
Soldiers. Invading a planet uses all invasion ships in the invading fleet and all soldiers. The workers (idle+busy) and soldiers on the surface of the planet automatically defend against invasions.
The attacker will loose 1 soldier for every 15 hostile workers to kill and 3 soldiers for every 2 defending soldiers.
| Attack & Defence | ||||
| Name | Attack Points | Defence Points | 1x Kills Defending  |
1x Kills Defending |
|---|---|---|---|---|
| Worker |
0 | 2 | - | - |
| Soldier |
30 | 45 | 15 | 0.66666 |
Successful invasion
The invasion is successful if the attacker kills every soldiers and workers in the planet. Then, the attacker takes control of the planet and the resources stored on it.
Enemy ships in the orbit of the planet are not destroyed by invasion, so the combat will continue each turn as long as there are enemy fleets and military ships in one side.
Enemy ships that were left in the Ship Yard are destroyed during invasion.
Research points
The attacker also earns research points if invasion is successful:
- 1 research point per 1,000 enemy soldiers killed
- 1 research point per 100,000 workers killed
Invasion failure
If the invasion fails the defender keeps control of the planet.
The defender loses soldiers and defending workers, whose numbers depends on the number of invading soldiers. Workers are killed only after the attacker successfully killed all defending soldiers.
The attacker loses all soldiers and invasion ships that attacked.