Particles is designed off of the game Darwinia. The story takes off from the launchpad on demo two. During the last invastion at the Launchpad, a platoon of the red army, stowed away inside the cargo hold of the rocket. Before the group hid away they were busy sabotaging the rocket. When the group looked through a portal window, they saw squads fighting back on the launchpad...they hid away. Halfway along the Darwinian's jorney, the rocket developed trouble, caught on fire and a forced landing was made to the nearest system. It was their only hope. After the landing, one dark night. The red army troups slipped away...Only to return later in greater numbers.
Here is an in-game picture on the map Electrons.
Here the Red army has over taken the Darwinians
base.