Planetary Combat

Once you are at with an empire you may attack any  or Colony in one of their systems by clicking on it. After defeating any enemy fleet present in Oribital Combat, you may then Bomb, Raid, and/or Invade the Colony depending on the ships present, or simply capture or destroy an with any ship.

Orbital Combat
You must first defeat any enemy fleet in the System in Orbital Combat around your selected target. This proceeds like a normal battle, though the enemy will gain bonuses from any or  present. If successful, you may begin Ground Combat.

Bombing
Bombing requires at least one ship with a, which can drop up to 3 bombs in a turn. These can be targeted at, , or. Mass Destruction increases the chance of success but can also lower the of the planet. Defenses against bombing include buildings such as.

Raiding
Raids require at least one to initiate and may damage the colony, capture a, or steal a technology or. An Assault Ship is lost during an unsuccessful raid. Buildings such as provide defense against raids. The Ground Combat Screen shows the chance of a successful raid. You may conduct both a raid and an invasion on the same turn.

Invading and Ground Combat
Invading a Colony seeks to capture or destroy it and also requires. Each provides a +5% GCB.

Ground Combat plays out automatically with no player intervention. The number of Marines participating in the battle is determined by the number of such ships present, and as Marines are lost those ships are destroyed. Both assault ships and planetary may be lost whichever side prevails.

Ground Combat Bonus
The Ground Combat Bonus or GCB determines the effectiveness of on planets and during.

For defenders bonuses may be gained from buildings such as and  as well as some  traits.

Both sides gain Ground Combat Bonuses from various technologies such as, , , , and. The Commando secondary skill provides a further bonus.

For only,  will increase the number of troops participating in the combat.