You can find the last version here: SpaceZero homepage


SpaceZero is a Real Time Strategy 2D space combat game for a single or two players over a network.
Your objective is to conquer all space.

At the starting point the player owns a spaceship which has landed on a planet.

Your first task is to acquire new spaceships and find new planets in the Galaxy.

By pressing key "o", a command menu will be displayed at the bottom of the main window. You can buy towers to extract resources and get more gold, explorers and fighters to explore and conquer the Galaxy.

After selecting an order press "ENTER" to execute it.

Press "ESC" to cancel it.

Pressing any of the navigation spaceship keys (key arrows and space bar by default) to control the spaceship manually. Press the "down key arrow" to return to automatic mode.

In manual mode you can control every spaceship independently. To turn the spaceship right or left use the arrow keys. In order to accelerate, use the up key arrow. SPACE to fire. "1", "2", "3", to change weapon.

By pressing key "M", a map of the known Universe will be displayed.

See Keyboard control for more options.


There are five types of spaceships: Explorer, Fighter, Defence Tower, Queen spaceship and defence satellite.


Useful to explore the space. It has a low gas cost and poor weapons. It has a large radar.


Better weapons and faster than the explorer.
Defence Tower

Defence Tower

The Defence Tower can only stay on planets. It has two objectives: the defence of the planet and the extraction of minerals.

Queen spaceship

In queen mode game, if you lose it, you lose the game.


Opening up commerce between two planets. The gold earned is proportional to the distance between the two planets.
defence satellite

Defence satellite

Unmanned ship. Useful for space exploration and planet defence.

Other objects:



All FIGHTERS of level 1 or superior come equipped with a survival pod. When a spaceship is destroyed the pilot is ejected. This pilot will be able to survive in space during a certain time (around 5 min.). He can be rescued by another spaceship and returned to the ground where he will be able to acquire a new spaceship. The level of the new spaceship will be equal to the old one. Its experience is set to zero.


You must conquer them.


Everywhere. Destroying them, you get gold.

Ship Properties:

MassMax. velocity
WeaponsCargoRadar range
(in sectors)
Explorer ship


Fighter ship


10030shoots, missile, laser301
Tower ship

Defence Tower

Queen ship


Freighter ship


Defence satellite





Orders menu:

It is possible to give orders to spaceships: pressing the "o" key, an orders menu is displayed at the bottom of the main window. When you enter the order mode you only can give an order. You get out of the order mode in one of the following ways:
  • Executing the order. Pressing "ENTER".
  • Cancelling the order. Pressing "ESC".
  • Changing spaceship. Pressing: "TAB", "PageUp", "PageDown" or "Home".
Several orders are available:

GOTO You can send your spaceships to different targets in many ways:
  • Giving the target id. The target id can be a planet or another spaceship. Several spaceships can fly together if all of them have the same target id. Example: GOTO 23. Will go the object labelled with the number 23. It can be a planet or another spaceship.
  • Giving the sector coordinates separated by blank or coma. Example: GOTO 23,12
  • Go to the nearest planet with n. Example: GOTO n. Will go to the nearest allied or known free planet.
  • Instead of the spaceship id you can write F1, F2, etc. for the selected marked spaceships (see selecting a spaceship). Example: GOTO F3.
  • In map view, the right mouse button will send the selected spaceships to the mouse position. If the pointer is closer than 0.5 sectors to a planet or to one's spaceship then they will be sent to that planet or spaceship.
EXPLORE Your spaceship will take off and will explore space. Be aware if your spaceship runs out of fuel or if it is very far from home.
SELECT You can select a spaceship or a planet typing its id.
STOP Your spaceship will stop. Inside a planet, it will land first. Once stopped, it will only shoot, but will not accelerate.
  • Your spaceship will go directly to the nearest empty or allied planet, without attacking enemies or asteroids.
  • You can also assign a target planet adding its id after the order. Example: RETREAT 23 will send your selected spaceships to planet 23 (it can be allied or enemy).

    Once entering planet the order will be changed:

    • If the planet is empty or allied it will be changed to STOP.
    • In the case of an enemy planet, the order will be changed to GOTO, attacking the enemies.
TAKE OFF To take off.
ORBIT The Spaceship will take off and orbit around the planet. If it starts at outer space it will go first close to nearest planet.
It will never thrust while orbiting. Under attack it only turns and shot. With low ammunition, fuel or great damages, it will return to the nearest allied planet.
BUY You can buy any available spaceship, if you have enough gold. The spaceship must be landed.
If you are not in a planet of your own, you can't buy Towers.
The Pilots only can buy Fighters.
UPGRADE You can upgrade your spaceship until one level lower than the greatest level reached. The spaceship must be landed.
SELL To sell a spaceship. You'll get the half of its original value. The spaceship must be landed.
If it is not landed will be destroyed.
REPEAT Repeat the last order given.

Manual and automatic mode:

You can change between both modes, for all your spaceships, pressing any of the navigation spaceship keys (key arrows and space bar by default) for manual mode and give an order or press the "down arrow" key to go back to automatic mode.

Only one spaceship can be changed between these modes at a time. Inside a planet this special spaceship is drawn with white color. In the free space this spaceship is shown with the radar centered on it.

In manual mode you can control every spaceship independently with the keyboard. To turn the spaceship use the left and right arrow keys. To accelerate, the up key arrow. SPACE to fire. 1,2,3 to change armour.

In automatic mode, the spaceship follows your orders, except in the following cases:

  • If an enemy spaceship is near then attack.
  • If it is close to asteroids, it will go towards them.
  • If it has little fuel or no ammunition it will go to the nearest allied planet.
  • When landed, it doesn't take off until it obtains a minimum amount of fuel and ammunition.
When the exceptions finish, it will continue with the given order.

Special orders:

  • STOP:
    If the spaceship is in outer space: stop, doesn't accelerate but can fire.
    Inside a planet: it first lands and stays on the ground, it doesn't take off but can fire. It never takes off.
    The order STOP is applied except in the following cases:
    • if the spaceship has low ammunition, low fuel or is very damaged it goes to the nearest allied planet.
    The spaceship will go directly to their destiny without attack enemies or asteroids.

Selecting a spaceship:

There are several ways of selecting a spaceship:

  • Pressing the "Tab" key you can change between all your spaceships. "Ctrl-Tab" inverts the order.
  • Pressing "PageDown" selects a spaceship in the next planet. "PageUp" in the previous one.
  • Pressing "Home" selects the first spaceship in outer space.
  • Using the order command SELECT and introducing the spaceship ID.
  • With mouse. Left button selects the nearest spaceship to mouse pointer. This selected spaceship can be inside a planet.
  • There are four rapid access keys to select spaceships: F1, F2, F3 and F4. If you press Ctrl-F1 the actual selected spaceship is assigned to the key F1, etc...

Selecting multiple spaceships:

You can select various spaceships with the mouse. The next order will affect all of them. Simply, click with the left mouse button and, without releasing it, drag and select the region you want. All spaceships in this region will be selected.

You can select multiple individual spaceships keeping the "ctrl" key pressed.

If you select a planet in the map view, all spaceships inside the planet will be selected.

The color of the selected spaceships will be grey.

Selecting a target:

radar If the mouse pointer is close to a planet or one's own spaceship a red square signs the target objective. The right mouse button will send all selected spaceships to this target. This target can be a planet or any of your spaceships.

Over the mouse pointer is displayed: the space coordinates, the distance, in sectors from the selected spaceship to the mouse pointer and the id of the target.


The spaceships have three types of weapons.
ShotsAll the spaceships.
MissileOnly fighters.
LaserOnly fighters.

Depending on the level of the spaceship some weapons are available or not. At level 0 only the shots are available. The fighter has two more weapons: missile at level 1 and laser at level 2. All the spaceships increase their weapons strength and their shields when they get a new level.
In manual mode you can change amongst the weapons pressing 1, 2 or 3 keys (If the weapon is available or it has ammunition).

Defence satellites:

satellites In order to get defence satellites orbiting around your planets you must proceed as following:
  • Buy some satellites (spaceships must be landed).
  • Give them the ORBIT order.
  • Once the spaceships are orbiting eject the satellites pressing <Alt-s>.
You can destroy the satellites selecting and giving them the order DESTROY.
All the satellites that are far away from a planet will be lost.

Window and spaceship centered view modes.

Pressing "Ctrl-n" it is possible to change between two view modes: centered at the spaceship or centered at the window.

Game modes:

There are three game modes: Cooperative, Deathmatch and Queen mode.
  • Cooperative.

    You can select from the menu two options:

    1. Cooperative mode. In this case all human players fight in the same team.
    2. Computer cooperative mode. All computer players fight in the same team.
  • Deathmatch.

    It is the default mode. All the players fight against all.

  • Queen mode.

    A special spaceship plays the same role as the King in chess. If you lose it, all your spaceships are destroyed. GAME OVER.

It is possible to select these options from the command line: -cooperative, -compcooperative, -queen.

Navigate information:

Navigation information In normal navigation mode, in the left of the main window you can see the following information:
  • Three status bars: energy, state and experience of the current selected spaceship. The number next to STATE is the shield. A shield of 0.3 means that the spaceship receives 70% of the damage. The maximum value is 0.9.
  • Information about the current selected spaceship as the type of spaceship. Its ID. Its mode: Automatic (A) or Manual (M) and its level.
    Ammunition of the current selected weapon (damage) and weapon selected.
    In which sector it is, velocity, number of enemies killed, actual order, distance and time remaining to reach the target.
  • Global information about the player: gold, number of planets, number of spaceships, number of enemies defeated, number of spaceships lost and points.
  • Information about the planet in which the spaceship is. Planet ID, gold remaining, resource, mass and the level of the highest level spaceship. The resource indicates the number of towers that can be built in the planet. More towers can still defend the planet but don't extract more gold.


radar In the free space the radar info is shown as a red circle centered at the spaceship. The different objects are represented as follows: big dots for planets, with the color of the player that owns such planet. White dots for the owned spaceships, blue dots the spaceships of the same team and red dots for the enemy spaceships.
The survival pods as flashing crosses.


Pressing the "m" key you enter in the map view. All your spaceships and all known planets are shown.
It is possible to zoom in and out with "z" and "Z".
The cursor keys allow you to move along the map.
<SPACE> centers the map on the current spaceship.
Over the mouse pointer the space coordinates and the distance in sectors from the selected spaceship to the mouse pointer are displayed.

radar The white color is reserved for empty planets and asteroids. The different objects have the color of their player. The planets are represented by big dots, the spaceships by crosses, the asteroids by white crosses, the astronauts in free space by flashing crosses. The spaceships and planets also have their own id number.

The explored universe is marked with dark red crosses. The universe has a limit; beyond that there are no marks and no objects.

radar If the mouse pointer is close to a planet or one's own spaceship, a red square signs the target objective. The right mouse button will send all selected spaceships to this target. This target can be a planet or one's own spaceship.

Game messages:


All information about the game as: spaceships in danger, asteroids found, planets discovered, etc. appears in the bottom left corner of the main window.

Pressing the "f7" key a log message window will pop up. It shows the last 200 game messages.

If you run SpaceZero from a terminal the same information is displayed on it. All the given orders accepted are also shown there.

Spaceships and planets info:

Pressing the "f5" key short information of all your spaceships and planets is displayed.

Ship list
    In the left of the main window you can see the following information about your spaceships:
    The first line shows the total number of spaceships and the number of each type.
    There is a line for every spaceship with the following information:
  • The type of the spaceship and its level: F (fighter), T (tower), E (explorer), Q (queen) , A (astronaut) or M (if it is in manual mode).
  • Its ID.
  • The actual order. EXP means exploring. GT:14 that is going to obj 14.
  • In which planet is the spaceship. IN:0 means in outer space.
  • If the spaceship state or energy are not at 100% it is showed these values.
  • In white color its shown the actual selected spaceships. Red and yellow colors are for spaceships in danger (cause of low gas or damaged). The pilots and spaceships in manual mode are shown in red. In blue the allied ones.
planet list In the right side of the screen is shown a planet list with the next information: planet id, gold remaining and the number of spaceships in it.
The number of spaceships in outer space is showed in the second line.

Pressing the "f6" key a sort game statistics are displayed with the next information:

game statistics

In the left window: the historic values of the sum of the level of all spaceships.

In the right one: Player name, [player level : sum of the level of all spaceships : average level], number of spaceships, (total number of spaceships created), planets, enemy destroyed and number of lost spaceships.

Pressing the "ESC" key all the info windows are closed.

Repairing spaceships:

The spaceships are repaired, refueled and rearmed while are on ground.
In space, can be done little reparations. They obtain also some energy.

Experience and Levels:

Spaceships experience increase during the game. When a spaceship reaches a maximum is upgraded to the next level. This way it can get new arms, better defence and more power. If a spaceship is upgraded, its state and energy is restored to the maximum value.

The spaceships can get experience in any of the following ways:

  • In combat, when a spaceship is reached by a shot, destroying an enemy spaceship and conquering an enemy or empty planet.
    When a spaceship conquer a planet there is a probability to received info from enemy (the coordinates of some planet). This probability increase with spaceship's level.
  • Exploring: Discovering new planets.
  • Training: all spaceships with a level equal or superior to 3 can train other spaceships. For training, both spaceships must be in same planet and the pupil must be landed. The master also must be two levels superior. The spaceship must be totally repaired.
  • Trading: Every time a Freighter complete a trip increased it experience.
  • Upgrade: you can upgrade a spaceship (it cost gold). You can only upgrade until one level below the player level.

Player level:

The player level is the maximum level reached for one of your spaceships. The level of the player will be increased only when the spaceship lands.


There are several ways to obtain gold:

-Every tower in each planet gets gold until the planet resources are finished. In this case they can still obtain a little amount of gold. Increasing the number of towers in every planet increased the amount of gold obtained. Depending on the planet mass, there is a limit in the number of towers in the same planet that can obtain gold. For the big ones, this limit can be four or five towers. For the little ones, three.

-For each planet, every player gets a fix amount of gold.

-Destroying asteroids is another way to obtain gold.

-Trading: when a Freighter spaceship reach a planet, the planet resources are increased.

-All the spaceships destroyed inside a planet increase the planet resources.

-And the last way: selling spaceships .

And there are also several ways to lost it:

-All the spaceships, except the towers, have a cost. This constant cost is increased when a spaceship is upgraded.

-All the ammunition cost gold.

-Repair and refuel a spaceship cost gold.

-Buying, upgrading spaceships.

Exploring the Universe:

The explore skills depends on the level of the spaceship:
  • level 0: a random walk.
  • level 1: try to find an unknown sector near their position. if there no one: random walk
  • level 2 and greater: looks for an unknown sector further than the previous level. If there no one: random walk
The explorers increase in one their skill value: an explorer of level 0 has a level 1 on explorer skill. A fighter of level 0 has a level 0 on explorer skill.

Size of the Universe:

Its possible to choose the size of the Universe, the number of galaxies and the total number of planets. Use the command line options: -l, -g and -n.

The units of the universe size are pixels. The distance is indicated in sectors (1 sector is 1410 pixels)

Net gaming:

For two players net game: one must be configured as the server and the other one as the client. Use the next command line options:

$ spacezero -s -ip ipnumber
for the server, and

$ spacezero -c -ip ipnumber
for the client.

where ipnumber is the IP number of the server.

SpaceZero use the port 50100 by default. You can use another port adding -port portnumber in the command line. SpaceZero also use the next port, by default 50101.

Saving game options:

By default the options are saved when the game starts. A new game starts with the previous game options.

Loading and saving games:

<Ctrl>-s and <Ctrl>-l will save and load a game. Only two games can be saved: one for single games and another one for a net games.
In a net game only the server can save and load games.

Pausing a game:

<Ctrl>-p will pause the game.

Quitting a game:

<Ctrl>-q will quit the game.

Game Over:

If you lost all your spaceships the game is over.

In queen mode game, if you lost the Queen Spaceship, you lost the game.

When game is over, pressing the "f9" and "f10" keys you can observe the other players (in single games and in the server side).


-Try to conquer all the inexplore planets as fast as you can.

-Don't buy more than two or three towers by planet unless you need to defend the planet.

-Watch out your explorers, don't let them go too far.

-You can form groups of spaceships ordering to some of them GOTO another spaceship. All of them will go where this last one go.

-Save some gold. It would be useful if you are under attack.

-Use the spaceships of level three or superior to upgrade the rest, especially the towers.

Keyboard controls (default values):

up arrow accelerate/manual mode.
left,right arrows turn left, right/manual mode.
SPACE fire.
1, 2, 3 choose weapon.
o enter in order menu.
Esc exit from order menu.
cancel an order.
close info windows.
tab change to next spaceship.
Ctrl-tab change to previous spaceship.
PageDown change to next planet.
PageUp change to previous planet.
Home change to first spaceship in outer space.
Ctrl-[f1f2f3f4] mark a spaceship.
f1, f2, f3, f4 select a previous marked spaceship.
f5 show a spaceship list.
f6 show game statistics.
f7 show game messages log.
m show-hide space map.
arrow keys, SPACE/down arrow manual/automatic mode.
Alt-s Eject satellite.
Alt-p Eject Pilot.
Ctrl-w write a message to the other players.
Ctrl +/- sound volume.
Ctrl-n window, spaceship mode view
Ctrl-p pause game
Ctrl-q quit game.
Ctrl-s save game.
Ctrl-l load game.

In map view:

z Z zoom in out.
arrow keys move map.
SPACE center map on the current spaceship.
mouse pointer show coordinates.
l show-hide labels.
left mouse buttonselects the nearest spaceship to mouse pointer.
right mouse buttonsend selected spaceships to pointer coordinates.

Command line options:

Usage is: spacezero [GENERAL OPTIONS] [GAME OPTIONS]
spacezero -h

-s Server mode. (multiplayer)
-c Client mode. (multiplayer)
-h This help.

-soundvol n where n is the sound effects volume. (0..100)
-musicvol n where n is the music volume. (0..100)
-nosound. Sound disabled.
-nomusic. Music disabled.
-nomenu. Starts automatically, without menu.
-name playername. Where playername is the name of the player.
-font font. Change the default font by font (XLFD format).
-lang [en,es]. Game language. English(default) and spanish supported.

-geom widthxheigth. Define the size of the main window.
-n n. Where n is the number of planets.(2..200, default 30)
-p n. Where n is the number of players.(2..8, default 2)
-g n. Where n is the number of galaxies.(1..10, default 1)
-l n. Where n is the size of the Universe.(10000..1000000, default 100000)
-k. Planets are known by all the players.
-cooperative. Cooperative mode.
-compcooperative. Computer cooperative mode.
-queen. Queen mode.
-pirates. Add a team of pirates (default).
-nopirates. Don't add a team of pirates.
-enemyknown. All enemies are known.
-noenemyknown. All enemies are unknown (default).

-ip IP. Where IP is the ip of the server.
-port n. Where n and n+1 are the used ports. (default 50100).


Not so tested in net between 32 and 64 machines. Maybe doesn't work properly.

Not so tested in an internet connection. Maybe doesn't work properly.

Please, send bugs using the sourceforge tracking tool:
Send bug

Use the Feature Request tool from sourceforge to send suggestions

Or send bugs and suggestions to <mrevenga at>.