SpaceInvasion is a free to play

Freeware

Freeware is computer software that is available for use at no cost or for an optional fee, but usually with one or more restricted usage rights. Freeware is in contrast to commercial software, which is typically sold for profit, but might be distributed for a business or commercial purpose in the...

, text-based resource management and space-war massively multiplayer online

Massively multiplayer online game

A massively multiplayer online game is a multiplayer video game which is capable of supporting hundreds or thousands of players simultaneously. By necessity, they are played on the Internet, and usually feature at least one persistent world. They are, however, not necessarily games played on...

 browser game

Browser game

A browser game is a computer game that is played over the Internet using a web browser. Browser games can be created and run using standard web technologies or browser plug-ins. Browser games include all video game genres and can be single-player or multiplayer...

 purchased and relaunched by Bigpoint in 2007. It has many gameplay features similar to OGame

OGame

OGame is a text-based, resource-management and space-war themed massively multiplayer online browser game with over two million accounts. OGame was created in 2000 and is produced and maintained by Bioware.. OGame is available in multiple languages, and different nationalities have their own...

. The game world is entirely controlled by human players; there are no NPCs

Non-player character

A non-player character , sometimes known as a non-person character or non-playable character, in a game is any fictional character not controlled by a player. In electronic games, this usually means a character controlled by the computer through artificial intelligence...

 in the game.

Gameplay

After the player registers for a universe and logs in, a random planet is assigned to them. There are 16 planets in one solar system and 400 solar systems in one galaxy. There are a total of 14 galaxies in one universe.

All starting planets have 230 fields. Fields determine the amount of buildings a player can have on the planet. Four resources, Pig Iron, Metal, Kryptonite, and Spice are used to construct buildings, upgrade research and create ships. Resources are gained by production from mines, trading, or from battle. Players are ranked in a point system: for every 2000 units of resource spent on construction one point is gained. Points determine which players can attack one another; players with significantly higher points cannot attack a player with much lower points and vice versa.

The game is a persistent world

Persistent world

A persistent world is a virtual world that continues to exist even after a user exits the world and that user-made changes to its state are, to some extent, permanent...

so construction, research, and production will continue even when the user is offline. This also means that a player may be attacked anytime; to counter this, almost all players "escape flight" whenever they go offline or are away from the computer. In an escape flight, the player sends his their fleet and resources to another planet. The speed is set so the fleet will return when the player is able to return to the computer. This prevents the player from losing their fleet while they are offline.

Combat

Combat happens when a player sends an attacking fleet to another planet. The battle is calculated by the number and strength of both fleets in a maximum of 6 rounds. The battle ends when one side is completely destroyed or the 6 rounds are over (whichever comes first). When an attacker wins the battle, half of the defender's resources are captured and the attacking fleet returns to the starting planet. Only ships and defenses can be destroyed in battle; buildings do not take damage.

Resources

There are currently 4 resources used in SpaceInvasion: Pig Iron, Metal, Kryptonite, and Spice. All of them can be gained through mining except Metal, which is produced from Pig Iron using a Blast Furnace. For mines to function, the player needs Energy. Energy can be created from Fusion Plants, Thermosolar Plants or Solar cells. Solar cells are ships and therefore can be destroyed. All resources can be gained from attacking another player (as long as the defender has the resources present). Metal and Kryptonite can also be retrieved from a destroyed fleet using Recyclers, a type of ship.

Alliances

An alliance is a group of players who have banded together. In the alliance, members cannot attack one another. Privileges, such as viewing the information of other members or sending alliance-wide messages, can be changed for each member by the alliance leader. If a player has an asteroid, members from the same alliance can station their fleets on the asteroid for an alliance attack.

Asteroid

An asteroid can be formed when rubble is created; the more rubble present, the higher the chance of an asteroid forming. Asteroids belong to the planet which it formed over. The Galaxy Scanner is a building that can only be built on the Asteroid. This building can scan for fleet movements near the asteroid, showing the asteroid owner the information