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Space Empires 4X


Space Empires 4X is a game in the 4X empire-building genre (eXplore, eXpand, eXploit, eXterminate) for one to four players. Eliminating your opponent's Homeworld wins you the game. Beginners should start with the Basic Rules. The galaxy game board is made up of hexes and your pieces are square counters (aka chits or tokens). All dice rolls in the game are done with a 10-sided die and "0" equals 10.

Game Start

Choose the hex in your Home System where you'd like your Homeworld to be located. Once all players have made their choice, the galaxy populates with random hidden counters (square tokens) and your Homeworld will appear with the following units:

  • Shipyard
  • Miner
  • Scouts (x3)
  • Colony Ships (x3)

Sequence of Play

Space Empires 4X is played with 3 normal turns followed by an Economic Phase and then repeated. On turn one, a die is rolled to determine first player. In future turns, first player is determined through bidding in the Economic Phase.

  1. Determine player order
  2. Turn One:
    • Player 1
    1. Movement
    2. Combat
    3. Exploration
    • Players 2-4: Same as Player 1
  3. Turn Two: Same as Turn One
  4. Turn Three: Same as Turn One
  5. Economic Phase: All players conduct this phase simultaneously.


Your units can move into adjacent hexes based on your Movement Technology Level, which starts at 1 hex. During your Move phase you can move one, some, all, or none of your units. When you develop your Movement Technology and Upgrade your ship(s) you are able to move additional hex spaces:

  • Level 2: Ships move 1 space in turns 1-2 and then 2 spaces in turn 3.
  • Level 3: Ships move 1 space in turn 1 and then 2 spaces in turns 2-3.
  • Level 4: Ships move 2 spaces in all turns.
  • Level 5: Ships move 2 spaces in turns 1-2 and then 3 spaces in turn 3.
  • Level 6: Ships move 2 spaces in turn 1 and then 3 spaces in turns 2-3.
  • Level 7: Ships move 3 spaces in all turns.

Mining Ships, Colony Ships, MS Pipelines, and Mines only ever move 1 space per turn. Bases and Ship Yards do not move.

Movement Restrictions

Units may not enter a hex with a face-down (unexplored) System marker, a Nebula, or Asteroids, unless it starts its turn adjacent to it. Entering a hex with any of these markers ends that unit’s movement, regardless of its Movement Technology Level.

Moving a unit without Attack Strength (ie: Miners, Colony Ships, or Decoys) into a hex with a face-down (unexplored) System marker, enemy unit, or enemy colony is not allowed unless a combat capable ship has also entered that hex.

Enemy Occupied Hexes

If you enter a hex occupied by a combat-capable enemy unit you must stop movement and attack during the Combat phase. If the hex is occupied by enemy units without combat capability, they are immediately destroyed and do not impede movement. You may ignore an enemy Colony and move through the planet or you may stop and attack it during Combat phase.

Planets and Colonization

Planets without Colonies do not affect your movement and may be Colonized by a Colony Ship. If a Colony is destroyed the planet may be re-colonized.

Initiating Colonization

Move your Colony Ship onto the Planet and Colonize it. Your crew will dismantle the Colony Ship to start your new Colony. Your Colonies grow during future Economic Phases, from 1 CP, to 3 CP, to 5 CP maximum.

Colonizing Barren Planets

You may encounter Barren (monochrome colored) planets while scouting. If you have developed Terra-forming Technology you can Colonize it just like a habitable planet. Once Colonized, it performs just like any other planet. If the Colony is destroyed, however, it will revert to a Barren Planet.


The Combat Phase occurs whenever two enemy units occupy the same System (hex). The player that moved into the occupied System is the Attacker. If there is more than one battle, the Attacker will choose the order. During Combat both attacker and defender will fire, often multiple times, until only one player remains in the System. Combat may last any number of rounds.

Combat Procedure

The Combat Phase window appears with opposing ships organized along battles lines and Class level (A through E). Any Decoy units are destroyed at start of Combat.

Combat Screening

A player with a greater number of Combat capable ships than their opponent may optionally choose to Screen ships from Combat (up to the difference in ship count). Screened ships may not fire or be fired upon for that Combat round and they may Retreat on their turn. Screened ships can be changed each Combat round. Non-combat ships are automatically Screened.

Fleet Size Bonus

At the start of each Combat round, if your fleet is twice as large as your opponent, your firing units receive +1 Attack bonus. Mines do not count towards Fleet Size.

Resolve Combat

Starting with your A Class units, and proceeding down through every Class, each ship has the opportunity to fire one time. A ship can be a target more than once. After the first round of Combat any firing unit may instead choose to Retreat.

Firing Order

Combat is not simultaneous. A Class fires before B, B fires before C, etc. If Combat units have equal Class, the units with higher Tactics technology fire first. If Combat units have equal Class and Tactics, the defender fires first.

If Combat occurs in a System (hex) occupied by Asteroids or Nebulae then all ships are affected and considered Class E no matter what their original Class.

Who May Fire

A unit (ship) with Attack Strength may fire at any opposing unit unless Screened. Ships in the same Group each fire and may choose unique targets.

Non-Combat Units

Colony Ships, Mining Ships, and MS Pipelines have no Combat ability and will be destroyed if caught alone or if all other Combat capable units are destroyed or retreat. They may not retreat. Colonies (planets) have no Combat abilities but are not automatically destroyed.

Fire Resolution

Select your Attacking unit and your target. Your Attack Strength is the sum of your unit's Attack Strength plus its Attack Technology Level. Add a +1 bonus if Fleet Size Bonus is in effect. Your target's Defense is the sum of its Defense Strength plus its Defense Technology Level and this result is subtracted from your Attack Strength to determine your "To Hit" number. A die is rolled for each attacking ship and must be equal or less than the "To Hit" number to succeed. A die roll of 1 will always hit.

Recording Hits

Damage is cumulative through Combat and once a ship's damage equals its Hull Size, it is destroyed. Ships in a group may only be targeted one at a time. Hits to a ship do not affect abilities or performance in any way.

At the conclusion of Combat, any surviving ships will send their crews into repair mode and all damage will be removed.

Special Conditions

When Combat occurs in a System with Asteroids, all ships are considered Class E and their Attack Technology Level is considered to be zero. Attack Strength is not affected. Fire order depends on Tactics.
When Combat occurs in a System with a Nebula, all ships are considered Class E and their Defense Technology Level is considered to be zero. Defense Strength is not affected. Fire order depends on Tactics.


After the first round of Combat, any Combat capable ship may instead choose to Retreat to an adjacent System (hex) which is the same distance, or less, from one of its colonies. That System must not contain enemy units or be an unexplored System. If there is no legal retreat System available, Retreat is not possible. Bases and Ship Yards cannot retreat, nor can Colony Ships, Mining Ships, or MS Pipelines as they are too slow. Be warned that this rule can lead to seemingly counter-intuitive retreats, which are perfectly legal: an enemy fleet CAN retreat towards one of your colonies if that square is at least the same distance from one of the retreating party's colonies. To stop this you may try to surround embattled hexes with weak or even non-military units (such as decoys, miners or scouts) which will prevent enemy forces retreating into their square. This discussion thread may be helpful:

Colonies and Combat

Once all ships in a System have been destroyed or Retreated, you may attack an enemy Colony or Homeworld. Each of your ships may fire once and the Colony cannot fire back (it has no Defense Strength or Defense Technology). The attacking ship's Attack Strength and Attack Technology are used to determine success at firing.

A hit will reduce the Colony one step (ie: 2), so a Colony with 5 CP is reduced to 3 CP, 3 CP is reduced to 1 CP, and 1 CP is destroyed if hit. A newly colonized Planet with a grounded Colony Ship on it also only requires one hit to destroy. The empty Planet may be colonized again in the future. Damaged Colonies function normally and will grow again in the next Economic Phase.

A hit will reduce a Homeworld one step (ie: 5), so a Homeworld with 20 CP is reduced to 15 CP, 15 CP is reduced to 10 CP, 10 CP to 5 CP, and 5 CP is destroyed if hit.

Post Combat

Ships revealed in Combat will stay face-up and can be examined by other players until they return to one of their Colonies where they can flip face-down again.


At the start of the game all Systems (hexes) are unexplored, except for the players' Homeworlds. If a unit (ship) lands on an unexplored space it must explore that system and apply any effects immediately.

Before beginning its movement, a Cruiser with Exploration Tech level 1 can 'explore' an adjacent hex by peeking at the counter there (on BGA, click as if you were moving into the hex, then click the 'use Exploration tech' button in the prompt area). It then has the choice to reveal or hide the counter. On BGA, if the Cruiser hides the counter, the counter remains hidden unless it is a Mineral 10 or a Space Wreck, in which case it is revealed during the Exploration phase of the player's third turn (unless a ship moves into the hex, of course). Also on BGA, it appears that a ship cannot move into a hex with a counter that has been peeked at and hidden, unless it begins the turn adjacent to that hex (perhaps this is a bug?).

Planets, Nebulae, Asteroids

  • Planets: Can be Colonized
  • Nebulae & Asteroids: Affect Movement and Combat


Mineral counters represent valuable resources. They do not affect Movement or Combat and cannot be voluntarily destroyed. Minerals can be towed away to one of your Colonies or your Homeworld by a Mining ship. Each Mining Ship can tow one Mineral counter. There is no cost to pick up or deposit Minerals. You may deposit more than one Mineral per Colony/Homeworld. During the Economic Phase they generate the amount of CP printed on the counter.

If a Mining Ship is destroyed while towing a Mineral, the Mineral is also destroyed. If a Colony with Minerals is destroyed before the Economic Phase, the Mineral is also destroyed.

Black Holes

Discovery of a Black Hole in a hex requires units to stop and make a roll to determine survival. Each unit must roll so observant enemies will see how many ships entered the System. A roll of 1-6 and the unit survives, 7-10 means the unit is destroyed. Surviving units may continue any remaining Movement. Black Holes remain for the entire game.


Space is full of danger. When this counter is discovered, all units there are destroyed. The hex remains empty in the future.

Super Nova

Super Novas dominate an entire sector. If a unit moving into a hex discovered a Super Nova, they must return to the hex they came from. Units may not move or retreat into a Super Nova. Super Novas remain for the entire game.

Lost in Space

When this counter is discovered by your unit(s), the player to your right shifts your unit(s) 1 hex in any direction. If that hex contains an unexplored system it must be explored. If it contains an enemy you must enter Combat. After leaving the Lost in Space hex, the counter is removed and the hex remains empty for the rest of the game.

Space Wreck

A Space Wreck can be picked up and deposited just like a Mineral. It will provide a free Technology upgrade instead of CP. To determine which Technology, roll a die and consult the list:

  • 1-2: Ship Size upgrade
  • 3-4: Attack upgrade
  • 5-6: Defense upgrade
  • 7: Tactics upgrade
  • 8-9: Move upgrade
  • 10: Ship Yard upgrade

If the Technology Level is already at maximum the free upgrade is wasted.

Economic Phase

During the Economic Phase you will see the amount of CP (Colonization Points) generated by your Homeworld/Colonies* and any Minerals you have deposited. You will also have a negative number, which is the cost to keep your fleet Maintained and is equal to your collective Hull Sizes (see below). You may also optionally bid any number of CP to win the choice of player order for the next 3 turns. If nobody bids or there is a tie, the current first player retains the position in first. The remaining CP balance can be spent on Technology Level upgrades and/or you can click on any of your Colonized Planets or Homeworld to see which ship units can be built there. Unspent CP can be carried forward to the next Economic Phase but never more than 30 CP.

* Colonies occupied by an enemy unit with Attack Strength are in Blockade and do not generate CP or Mineral income (they can still Grow, however).

Maintenance Costs

Each ship's Hull Size is equal to its maintenance cost. Bases, Colonies, Colony Ships, Ship Yards, and Mining Ships do not have a Maintenance Cost.

Purchase Units and Technology

Costs for Units and Technology are printed on the Ship Technology Chart and Research Chart. At the start of the game you may only build Scouts, Mining Ships, Colony Ships, Ship Yards, and Decoys. You may build other ships when you advance your Technology Levels.

Ship Technology Level

Building a new unit (Ship) automatically builds it at your current Technology Level. You can purchase a Technology Level and a spaceship in the same Economic Phase and it will have the latest tech. Ships already in play, however, are not automatically upgraded (unless playing with Basic Rules options that provide Instant Upgrades).

Purchase Limits

You may not build ships if all counters of that ship type are already in play (unless you Scuttle ships to reuse the counter).


Besides ships, you can spend your CPs on Technology Level upgrades. Refer to the Research Chart for each level's cost. Each Technology must be purchased in level order (no skipping over levels) and only one level of each tech may be purchased per Economic Phase.

Attack and Defense Technology

Improve your unit Combat abilities with these two techs. Note that your unit Hull Size limits your Attack and Defense levels to the same amount, never more. This is the only limit on technologies.

Tactics Technology

Units/Groups that have a higher Tactics level will fire first in Combat.

Ship Size Technology

In order to build larger and more powerful ships, you need to increase your Ship Size technology. You may use this new tech in the same Economic Turn it was purchased.

Movement Technology

This dictates how fast (far) your ship may move.

Ship Yard Technology

You start with a Ship Yard capable of building ships with a Hull Size of 1. Level 2 grants 1.5 Hull Size and Level 3 grants 2 Hull Size ships. Combine multiple Ship Yards on a Colony to build even larger ships.

Terraforming Technology

Once purchased, your Colony Ships can Terraform Barren Planets. Colony Ships built prior to upgrade do not have Terraform.

Exploration Technology

This tech provides your Cruiser Ships with advanced sensors which allow you to peek at one adjacent unexplored (face down) counter prior to moving. Once seen, you choose to reveal or leave it face down. If revealed and the counter has any immediate effect, it is discarded and any negative effects do not affect your Cruiser.

NOTE: This means that a Cruiser equipped with Exploration Technology can explore 2 hexes each turn (one with its Exploration Technology and one by moving into the hex).

See the Exploration section for additional notes regarding the use of this technology.

Playing Pieces

System Markers

Your Home System will contain randomly-placed face-down square counters. Each player's color (red, blue, green, or yellow) will show as an outline on the square counters within their System. The white-outlined counters between players' Systems are "Deep Space" territory.


Each player has one Homeworld, representing their starting planet/solar system from which they explore the galaxy. Each Homeworld produces 20 CPs (Construction Points). If your Homeworld is defeated by an enemy, you lose the game.


Planets have no function until Colonized. Some planets are Barren and cannot be Colonized until Terra-formed. Habitable planets have a color matching the player Home System.


A Planet that has been Colonized. Once populated, a Colony can grow from 1 CP, to 3 CP, to the maximum of 5 CP.


Your spaceships of the same type and Technology Level. Each spaceship Group can contain 1-6 units, which is hidden from the enemy until engaged in Combat. The backside of the counter only displays a ship, while the front contains all the details, including: Type, Class, Attack Strength, Defense Strength, Hull Size, and Group Number.

Miners, Colony Ships, and MS Pipelines* are always single ships.


The upper left corner contains the ship type followed by the group ID number.

  • BB: Battleships
  • BC: Battle Cruisers
  • CA: Cruisers
  • CV: Carriers*
  • DD: Destroyers
  • DN: Dreadnaughts
  • F: Fighters*
  • R: Raiders*
  • SC: Scouts
  • SW: Minesweepers*
  • SY: Ship Yards

* denotes Advanced Rules ship types


This letter determines which ship fires first in Combat (A goes before B).

Attack Strength - Defense Strength

The lower left corner contains two numbers with a dash between them. The first is your Attack Strength, which is the number you need to score a hit (a 4 means you must roll a 4 or less). The second number is your Defense Strength, which modifies the attacker's die roll, making it harder to hit your ship(s).

Hull Size

The number in the lower right with an "x" is your unit Hull Size and indicates how many hits a ship in the group can take before being destroyed. Hull Size also determines the maintenance cost of the ship, the amount of technology that a ship can utilize, and the construction capacity needed to build a ship at a Ship Yard.

Special Unit Types


A Base is a defensive unit designed to protect a Colony. Only 1 base may be built per incoming-producing Colony (ie: not a brand new Colony) and it cannot move or retreat. A Base does not require a Ship Yard to be built. Does not have a maintenance cost.

Ship Yards

Ship Yards can only be built on an income-producing Colony, one per Planet. Additional Ship Yards (needed to increase Hull Size production) may be built in future Economic Phases. As Ship Yards are placed along side other units, they cannot produce new Units in the same Phase as their placement. Does not have a maintenance cost. Decoys, Bases, and Ship Yards to not require a Ship Yard to be built.


Decoys are unarmed, expendable ships that look just like larger ships or Groups to your opponents. Decoys do not explore, attack, or defend. They always move at the speed of your current Movement Technology Level. Decoys are revealed and destroyed if encountered alone by the enemy (enemy does not reveal themselves). If a Decoy is part of a friendly Group in Combat, it will be destroyed at start of Combat. Does not have a maintenance cost.

Colony Ships

Colony Ships always represent a single ship, always stay face-up, and always move just 1 hex per turn. They flip to their Colony side once they Colonize a Planet.

Mining Ships

Mining Ships always represent a single ship, always stay face-up, and always move just 1 hex per turn. They are used to tow a Mineral or a Space Wreck counter back to one of your Colonies. Does not have a maintenance cost.


  • Construction Point (CP): Your Homeworld and your Colonies (planets) produce Construction Points, which are used in the Economic Phase to purchase units, maintain your fleet, and develop technologies.
  • Enemy: Any other player's unit(s)
  • Group: A counter (token) that represents 1-6 spaceships of the same type. A group can be a single ship as group size is usually hidden from the enemy.
  • Home System: The group of hexes where your Home System and Homeworld markers are placed.
  • System: A single hex on the board.
  • Unit: A Group, Decoy, Miner, Colony Ship, Base, Ship Yard, or MS Pipeline.