The Mission begins in Prebuild, where the player can "pre-build" structures and units before the player's forces actually land on the planet.  The player is actually looking at a topographical map of the landing site and planning which structures and units will be "tightbeamed," or teleported, to the site.  The player should start by building the essentials needed to defend and build a base; a couple of Cryofarms, a Vehicle Factory, a Parts Factory, Assembly Bay, a Combot, and lots of Hovertrucks!