In most 4X games, the space between systems did not exist - ships could fly only from system to system and combat takes place only within them. This was not true in "Pax", where ships could be flown to any point on the game map. The flexible design allowed for a number of different strategies. For instance, inexpensive spy ships consisting of sensors and little else could be left in the outskirts of enemy solar systems to allow the player to examine what was going on in that system. On the other end of the spectrum, ships equipped only with shields and weapons, and no drive, could be used as defensive satellites.