PDS

PDS stands for Planetary Defense System. PDS was removed from the game with the introduction of PAX, round 10.

PDS were stationary defence, which meant you couldn't run them when faced with superior incoming. Because of this, people often didn't like to build PDS. PDS were more powerful than ships though and there were people who made a fortress out of this.

In round 3, 5:25 (called 'PDS Outpost') was PDS hogged. This allowed them to keep a lot of roids for their score, due to the massive losses attackers would suffer.

PDS served another purpose near the end of rounds by allowing players to spend their Eonium stockpiles to gain extra score.