The dominant gameplay of Star Control, and a significant portion of the gameplay of Star Control II is the space combat, fought between two ships in a wrap-around, 2D environment. The combat mechanics of this environment can largely influence the strategy and tactics used by players against the computer and against one another. These combat mechanics cover not just the standard units used, but also the behavior of colliding bodies and fired projectiles and the effects of gravity.
 Collisions and projectiles
In combat, collisions between ships and other objects appear to be nearly elastic and are governed by rules that closely resemble Newtonian mechanics. Most projectiles however obey a different set of rules entirely. The speed of a typical projectile is constant in the absolute reference frame defined by the planet and the background star field of the 2D environment, and is completely independent of the velocity of the firing starship. For some ships, this strange bit of physics has huge implications. A notable example is the Mycon Podship, which when moving at top speed and facing forward can overtake and be damaged by its own plasmoids.
Only the planet exerts a "gravitational" force on ships, projectiles and asteroids within the combat arena. This can be a hazard, pulling an unwitting captain or slow ship into a collision course with the planet. However, while being affected by a planet's gravity, a ship can achieve greater than normal speeds in a maneuver known as the Leyland Gravity Whip. Ships and asteroids can also become captured in stable, though usually eccentric, orbits about a planet. Notable exceptions to these effects are the Arilou Skiff and the Slylandro Probe, which are immune to a planet's gravity.
 Standard units
Most of the values for a ship's or projectile's abilities are given in terms of standard units.
- Frame rate
- In combat, the frame rate is 24 FPS (frames per second), i.e. a frame is 1/24 seconds. Rates, such as battery regeneration and turning, are determined by a minimum frame delay inbetween consecutive actions.
- World units
- Distances are measured in world units, which are equal to 1/4 of a pixel at full zoom with a 320x240 resolution. This applies directly to the maximum speed, which is expressed in world units per frame.
- There are only 16 possible facings for ships and projectiles, separated from each other by 22.5 degrees.
- See also: Super-Melee