How to Play
Generally, the space game runs almost identical to the ground. The GM still describes the environment, and the players describe what they want to do. The GM then narrates the results of of the adventurers' actions.
Space Versus Ground
The most important distinction here is the scaling down of the dice. An X-wing's laser cannon deals 1d6 to an enemy X-wing. The perspective for damage here is space. If you need to scale ships to the perspective of players, you want to scale the damage, hit/hull points, shield points, damage reduction, and shield regeneration rate of ships by 10, and vice versa. For Instance, an X-wing's primary weapon may deal 1d6 to ships, but would deal (1d6)x10 to a player, while a player's explosion power would instead deal (8d6)/10 damage (round down) to the X-wing. Because of their size and durability, some GMs may rule that Large and larger ships are simply immune to damage from small arms fire. Additionally, a Tiny starship is Tiny on the space scale, but Huge on the ground scale. Consequently, a Small ship is Gargantuan on the ground scale. Medium and larger ships would be considered colossal. Because starships are not primarily designed to fight individual creatures, Tiny-Large Starships have disadvantage on attacks versus Large and smaller creatures (and such creatures have advantage on saves caused by these ships' weapons).
Game Dice
The game uses the same polyhedral dice with different numbers of sides, referenced in the same fashion; the different dice are referred to by the letter d followed by the number of sides: d2, d4, d6, d8, d10, d12, and d20.
The D20
The same d20 that a Jedi uses to swing his lightsaber is used for firing a ship's weapons. The biggest deviation here is that when a player fires a ship weapon, they use the player's proficiency bonus, but the ship's Wisdom bonus. The reason for this is two-fold:
1. In the ground game, some Ability scores are stronger than others. Since this ruleset is designed to enhance the way the game is played, one character should not be penalized for being slightly different from another character.
2. How accurate a ship's weapons are is modified by the ship's targeting system. A ship with a higher Wisdom is more capable of accurate targeting than a ship with a low Wisdom, consequently yielding a greater likelihood of accuracy.
This and other deviations will be discussed at greater length in Chapter 7: Using Ability Scores.
Advantage and Disadvantage
Advantage and Disadvantage function identical to the ground game; with advantage, you roll two dice and take the higher value, while with the disadvantage you roll two dice and take the lesser.
Specific Beats General
In the same vein, while latter chapters contain broad strokes for the game's rules, certain deployment or ship features override those rules, creating an exception to how the rest of the game works. Remember this: if a specific rule contradicts a general rule, the specific rule wins.
ROUND APPROPRIATELY
Follow standard rules for rounding; if a number ends in one-half or greater, round up, while if a number ends in less than one-half, round down.