The strategy and tactics of war lend themselves perfectly to rigorous analysis, especially when treated separately from the more inexact world of diplomacy and negotiation. This chapter will describe the different tactics available to a bellicose emperor or empress and evaluate their effectiveness.
Before a fleet enters combat it must be split into attack groups so that each group is able to attack a target independently. Groups may only consist of one type of ship and no more than nine groups may be created. The standard configuration places each type of ship in one group, but you may want to split a fleet into more groups. For example, suppose that you have 1,000 fighters and 2,000 jumpship. The standard configuration creates two groups, one with fighters and one with jumpships, but this means that you can only attack two targets at once. If you were to split up the fleet into four groups, you would be able to attack four different targets.
The aim of the fleet commander attacking a planet is to land transports on the surface and disgorge the infantry legions that will conquer the world. But to do this the attack groups must first fight their way through the orbital defenses of the planet.
The space around the planet is divided into five locations: deep space, high orbit, standard orbit, low orbit, and ground level. The attack groups start in deep space and must fight the defenses at that location before proceeded to the next position. Each location is defended by any ships based on the planet (according to the empire's defense configuration orders) and is also defended by any ground defenses that can reach the location. Attack groups can target any ship or ground defense at their location.
See the chapter on ground defenses for a description of each kind of defense and the orbits at which they can attack and be attacked.
Each attack group may target an enemy ship type or ground defense. For example, a group of jumpships may target all enemy starships at the same location. Similarly, the defenders will split their forces to target each attack group. During each combat round attackers and defenders engage in battle and cause casualties according to the number and type of ships involved.
An attack group may be assigned to no target. In that case, the group actively avoids combat and effects defensive maneuvers. The extent to which a defending group is able to avoid damage depends on the power of other attacking groups. For example, a group of 100 transports can avoid damage if it is accompanied by a group of 1,000 starships that is attacking. Conversely, the group of 1,000 starships would not be able to avoid damage if the only attacking group is a group of 100 transports. Because of their size, transports and starships generally need many ships for cover; while starships and penetrators are generally good at providing cover.
Advancing Through Enemy Lines
Groups may advance through orbits that still have enemy defenders, but both sides will take increased damage. The close combat conditions increase the accuracy of a ship's weapons; damage sustained by both sides increases by 50%. Cloaked hunter-killer groups, however, can advance without taking damage.
Hunter-killer groups enter battle fully cloaked and remain cloaked as long as they do not attack. Once the group targets an enemy ship, however, the cloaking effect is lost. While cloaked, hunter-killers take no damage and may move through the orbits undisturbed.
Once transports carrying infantry land on a planet they become a group of infantry (or elite infantry as appropriate). Infantry groups can target other groups on the surface. If enough infantry has landed on the planet and it is able to destroy the defending infantry, then the world will quickly be conquered.
World class affects the fighting ability of infantry trying to conquer a world. A barren world, for example, which depends on complicated life-support equipment, is hard to defend because the population is so vulnerable. Ice worlds, on the other hand, are inhospitable to humans and machines, and thus provide the defenders with an advantage. Worlds that are difficult to defend include barren worlds, gas giant worlds, ocean worlds, and poisonous worlds. Worlds that are difficult to attack include desert, forest, ice, jungle worlds, and underground and volcanic worlds. Command bases and fortresses, as military installations designed to repel invaders, are the most difficult worlds to conquer; at least a two-to-one force advantage is needed to take over these strongholds.
Fleets Protecting Worlds
Fleets over a world protect that world from attack. Any enemy fleet that aims to conquer the world must first destroy all fleets in the sector. This property can be combined with the speed initiative of jumpfleets to protect worlds that are threatened. For example, suppose that you see an enemy fleet over one of your worlds. If you have a jumpfleet ready you can send it to the endangered world. Although you may not be able to attack the enemy before he or she attacks you, your fleet will be able to defend the planet.
Hunter-Killer Raiding Fleets
Since hunter-killers cannot be detected normally, they are ideal for surprise attacks on enemy fleets. Small hunter-killer fleets of 500 ships or less may be used as unflagged raiding fleets intended to instigate turmoil. Any attack by these small fleets will be reported to the enemy as attacks of unknown origin.
Long-range Attack Missiles are build by capitals and base planets and used as secondary defense against enemy fleets. Although they are only a little more powerful than GDMs, these missiles are equipped with miniature jumpdrive generators enabling the to hit targets up to five sectors away. As attack weapons they may be used preemptively to destroy enemy fleets that get too close. LAMs launched against a world will destroy the ground defenses of the world, but will do no other damage.