War

In the 2005 GDC Presentation, Will mentioned that in the Tribal Stage, players would send individuals from their tribe to conduct raids against other tribes.

In the Civilization Stage, he mentioned that war between civilizations would be conducted through Vehicles. It is not known if other options such as Infantry or Spies will be available.

In the presentation, Will's UFO visited an alien planet. After a negative encounter, the alien city began launching Missiles of some sort towards the UFO, suggesting that there may be some type of missiles available in the Civilization Stage as well.

=Planetary=

Possible Unit/Weapon Types
As of current, we know little of how we can conduct war, or if we will even have weapons other than vehicles.

Biological
It is unclear what alternative types of warfare will be available in the game.

Infantry/Hunting Parties
foot soldiers of the most basic kind, wielding whatever the player wishes him to. From spears to guns to lasers. It is unclear if Infantry will be in the game past the Tribal Stage.

Missiles
It is unclear whether or not there will be missiles in the game -- either one-time-use destructive vehicles, or weapons that can be launched from a stationary site (such as within a city or on a tower).

In the 2005 GDC Presentation, we can see the inhabitants of a city launch some sort of weapon at Will's UFO when he tried to communicate with them.

Spies
those who practice the art of espionage. It is currently unclear as to whether they shall be featured in Spore.

Stationary Weapons
Weapons of a defensive nature usually placed on a building or on/in/part of some other form of artificial or natural construction. In the Spore movie when Will Wright sent a UFO to another alien world he was fired upon with some sort of missile, from some sort of stationary objects on the ground.

Transformers
A special kind of Robot or Vehicle which can change between forms. A transformer may have artificial intelligence or not, and it may allow passengers or not. It is unclear if transformers will be available in the game.

=Galactic / Interstellar War= In the Gaming Steve Interview with Will Wright, Will stated that "[Galactic war] actually is a simple thing for us to do. So that is really more of a game design question." Further details on galactic war are unknown at the moment.