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Chapter 1: Overview

Getting Started

Source Starfinder Core Rulebook pg. 6
In Starfinder, you and your friends play the crew of a starship exploring the mysteries of a weird universe. Within this framework, however, there are no limits to the characters you can play and stories you can tell. Will you join the Starfinder Society in unearthing alien technology, or seek fame and fortune as a corporate mercenary? Perhaps you’re a Xenowarden fighting to protect the ecology of new planets, a mind-reading mystic detective, or an android assassin with a magic sword trying to atone for a dark past. Whatever your mission, you and your team will need all your magic, weapons, and wits to make it through. But most of all, you’ll need each other.

Before you can pick up your arc pistol and blast off toward adventure, there are some key things you need to know about running or playing in a Starfinder game. If you’re already experienced with roleplaying games, feel free to skip ahead to the next page.

What's a Roleplaying Game?

Source Starfinder Core Rulebook pg. 6
Starfinder is a tabletop adventure roleplaying game (RPG): an interactive story in which one player—the Game Master—sets the scene and presents challenges, while the other players each assume the role of a science fantasy hero and attempt to overcome those challenges. By responding to situations according to their characters’ personalities and abilities, the players help to create the story’s plot as the outcome of each scene (called an “encounter”) leads into the next. Dice rolls combined with preassigned statistics add an element of chance and determine whether characters succeed or fail at the actions they attempt. You can think of an RPG as theater: the players are the actors, while the Game Master is the director. But you don’t have to be a skilled actor or storyteller to play the game; just describe what you want your character to do, and let the Game Master and the rules do the rest!

The Players

Source Starfinder Core Rulebook pg. 6
Before the game begins, players typically invent their own player characters’ backgrounds and personalities. While it’s possible to play multiple characters at once, it’s generally the most fun to have one character per player, so players can really get into their roles. In addition to coming up with character concepts, players use the game’s rules to build their characters’ numerical statistics, which determine the characters’ abilities, strengths, and weaknesses. Chapter 2 provides in-depth instructions for how to create a character, pointing you toward relevant rules in other chapters. One of the reasons this book is so big is that there are tons of optional rules to help you customize an infinite variety of characters!

During the game, the players describe the actions their characters take. Some players particularly enjoy play-acting (or “roleplaying”) the game’s events as if they were their characters, while others describe their characters’ actions as if narrating a story. Do whatever feels best!

Many in-game situations in Starfinder have rules that govern how they’re resolved. When a fight breaks out, for example, the rules in Chapter 8 explain how to attack, defend, move, and so on. All the rules players need to play Starfinder can be found in this book.

The Game Master

Source Starfinder Core Rulebook pg. 6
While the rest of the players must create their characters for a Starfinder game, the Game Master (or GM) is in charge of the story and world. The Game Master is a player, but for the sake of simplicity, she is referred to in this book and other Starfinder products as the Game Master or GM, whereas the other players are referred to simply as players. The Game Master needs to detail the situations she wants the players to experience as part of an overarching story, consider how the actions of the player characters (or PCs) might affect her plans, and understand the rules and statistics for the challenges they will face along the way.

Many Game Masters find it fun and convenient to run premade adventures, in which the game’s story and mechanical preparation is largely complete. The Starfinder Adventure Path line fills this role nicely. Other Game Masters enjoy preparing original game material, and many use a blend of both methods. Either way, the rules in Chapter 11 help Game Masters figure out which characters or creatures are appropriate opponents for a given group of player characters, as well as how to adjudicate everything from zero gravity and environmental hazards to what sort of loot PCs should get as rewards for their accomplishments.

During the game, the players roll dice and use their player characters’ statistics to determine how in-game actions are resolved. Much like a referee, the Game Master is the final arbiter of any action’s success or failure, and she can always override the rules if she disagrees with an interpretation or feels a given rules interaction is breaking the mood.

Unlimited Adventure

Source Starfinder Core Rulebook pg. 6
A roleplaying game such as Starfinder can be played for as long as the Game Master has an ongoing story she enjoys exploring and advancing with her players. This means the game might last for a few hours, if the story is short and self-contained, or it might last several years. Each time the Game Master and players sit down to play, it’s called a game session—most sessions last several hours. Games generally consist of several linked sessions that together form a complete story, called an “adventure.” Short adventures that can be played in a single session are commonly referred to as “one-shots,” while games that last many sessions or contain several linked but distinct adventures are called “campaigns.”

What's in this Book?

Source Starfinder Core Rulebook pg. 7
This book contains all the information you need to play Starfinder, whether you’re a player or a Game Master. While some people may want to dive directly into the rules and character creation beginning with Chapter 2, others may want to first learn about Starfinder’s setting by perusing Chapter 12.

For players making characters, Chapter 2 provides a stepby- step walk-through of the process that includes references to relevant chapters. Chapter 3 follows with information about the different core races from which you can choose, and Chapter 4 presents classes that determine your character’s skills and abilities. Chapters 5–7 include information for further customizing your character’s abilities and equipment, while Chapter 10 covers magic and spells for characters with a supernatural element. Feel free to peruse some or all of these sections before embarking on the character creation process. See the first step in Character Creation on page 14 for more details.

Beyond information about character creation, this book also contains the rules you’ll need to play the Starfinder RPG. Tactical combat, movement, and related rules are an important part of Starfinder, as is starship combat, and these can be found in Chapters 8 and 9. It’s a good idea for players to review these chapters when learning how to play Starfinder, and it’s key for Game Masters to understand them so that gameplay and adjudication can flow smoothly.

Game Masters should also review Chapter 11, which collects key GM rules such as Starfinder’s common environments, hazards like traps and poisons, instructions for building encounters and preparing and running games, and more. They’ll also want to be deeply familiar with the setting presented in Chapter 12, and Game Masters familiar with the Pathfinder RPG and interested in bringing elements of that game into their Starfinder adventures will want to review Chapter 13, which explains how to incorporate legacy material into Starfinder.

Besides this book, you need just a few things to play and run a Starfinder game. Most importantly, you need a prepared Game Master and players with characters they’ve created ahead of time. (Blank character sheets can be found in the back of this book and online at You also need pencils and a set of polyhedral dice. Each die is referred to using a “d” followed by the number of sides it has (so a four-sided die is a d4). You need at least one d4, d6, d8, d10, d12, and d20, as well as a set of percentile dice (“d%”) that generates a number from 1 to 100 (this can be simulated with two 10-sided dice). You also need a tactical battle map with 1-inch squares and a starship battle map with 1-inch hexagons, as well as tokens or miniatures to represent your characters and ships.

Not sure where to start? Starfinder Flip-Mat: Basic Terrain and Starfinder Flip-Mat: Basic Starfield give you the maps you need to play, and you can find miniatures and cardstock pawns like the Starfinder Core Rulebook Pawn Collection at, along with dice sets and other gaming accessories.

Some Basic Concepts

Source Starfinder Core Rulebook pg. 7
To make the best use of this book, you’ll want to be familiar with several key terms and abbreviations. These are used throughout the book, and many are common to tabletop roleplaying in general. For a larger glossary, see page 512.

1d6, 1d20, etc.

Source Starfinder Core Rulebook pg. 8
These figures are abbreviations for die rolls and indicate which dice you roll to determine a variable number, such as the amount of damage a weapon deals. The first number tells you how many dice to roll, while the second number tells you the number of sides the die or dice must have; if there’s no first number, just roll one die. For example, “roll 2d8” means that you must roll two eight-sided dice, and “roll a d20” means you must roll one 20-sided die. Occasionally, you may need to roll a d3; if you don’t have a three-sided die, you can roll a d6 instead—treat a roll of 1 or 2 as a 1, a roll of 3 or 4 as a 2, and a roll of 5 or 6 as a 3.


Source Starfinder Core Rulebook pg. 8
Starfinder has many game terms that are typically expressed as abbreviations, including HP (Hit Points), SP (Stamina Points), and RP (Resolve Points). If you miss or forget what an abbreviation means, they’re explained in the glossary starting on page 512.

Armor Class (AC)

Source Starfinder Core Rulebook pg. 8
This is a number representing how hard it is for an enemy to strike your character in combat. A character has two Armor Classes: Energy Armor Class (EAC) and Kinetic Armor Class (KAC).

Attack Roll

Source Starfinder Core Rulebook pg. 8
An attack roll is a d20 roll that represents your character’s attempt to strike another creature in combat.


Source Starfinder Core Rulebook pg. 8
A check is a d20 roll that may or may not be modified by your character’s statistics or another value. The most common types are skill checks and ability checks (which determine whether you successfully perform a task), and initiative checks (which determine when you act in combat).


Source Starfinder Core Rulebook pg. 8
Typically, references to combat refer to tactical combat between individual characters, which takes place on a square-gridded battle map and is covered in depth in Chapter 8. Combat can instead refer to starship combat, which uses a hex map; you can find the details of that system in Chapter 9.


Source Starfinder Core Rulebook pg. 8
A creature is an active participant in the story or world. This includes player characters (PCs), nonplayer characters (NPCs), and monsters.

Difficulty Class (DC)

Source Starfinder Core Rulebook pg. 8
This is the target number a creature must meet or exceed when attempting a check in order to accomplish a given task.


Source Starfinder Core Rulebook pg. 8
An encounter is a situation that presents characters with a challenge. This could be a roleplaying challenge where they need to get information, a physical battle, a trap or puzzle, or anything else that requires players to use their wits or their characters’ statistics. Characters typically earn experience points for completing encounters.

Experience Points (XP)

Source Starfinder Core Rulebook pg. 8
Often just called “experience,” this is a way of tracking your character’s increasing expertise gained as a result of overcoming challenges. When characters earn enough experience points, they advance in level, or “level up” (see Leveling Up on page 26).

Game Master (GM)

Source Starfinder Core Rulebook pg. 8
The Game Master is the player who adjudicates the rules and controls the various elements of the Starfinder story and world that the players explore. A GM’s duty is to provide a fair and fun game—she wants the other players to ultimately succeed in their goals, but only after much heroic striving and danger.

Hit Points (HP) and Stamina Points (SP)

Source Starfinder Core Rulebook pg. 8
Stamina Points represent how much damage you can take before you’re actually hurt, while Hit Points represent how badly hurt you can be before you fall unconscious or die. Stamina Points are lost before Hit Points and are much easier to regain. For a more detailed explanation, see page 22.


Source Starfinder Core Rulebook pg. 8
A level is an indication of relative power within the game. There are several types of levels. Class level is the number of levels of a specific class that a character has. Character level is the sum of all of the levels a character has in all of her classes. Level can also refer to a spell’s level, an item’s level, or another scaling mechanic that falls within the framework of the game’s rules.


Source Starfinder Core Rulebook pg. 8
A modifier is a number that is added to a roll such as an attack roll, saving throw, or skill check. It can be positive or negative.


Source Starfinder Core Rulebook pg. 8
A monster is a nonplayer character. In general, monsters are too strange or unintelligent to be player characters, or are prevented from being them for other reasons. A monster might be a player character’s opponent or ally, or serve any other role.

Nonplayer Character (NPC)

Source Starfinder Core Rulebook pg. 8
A nonplayer character is controlled by the GM for the purpose of interacting with players and helping advance the story.

Player Character (PC)

Source Starfinder Core Rulebook pg. 8
This is a character controlled by a player.


Source Starfinder Core Rulebook pg. 8
Describing a character’s actions, often while play-acting from the perspective of the character, is referred to as roleplaying. When a player speaks or describes action from the perspective of a character, it is referred to as being “in character.”


Source Starfinder Core Rulebook pg. 8
In tactical combat, a round is a unit of time equal to 6 seconds in the game world; every character who is able to act gets a turn once per round. In starship combat, rounds consist of three phases of actions and don’t correlate to a specific amount of time.

Saving Throw

Source Starfinder Core Rulebook pg. 9
A saving throw is a d20 roll representing your character’s attempt to avoid or reduce some harmful effect.


Source Starfinder Core Rulebook pg. 9
Tier indicates scaling and is similar in meaning to “level”; it is used for computers and starships, as well as other elements.