Hi,
From time to time fleet meet enemy ships in expedition.
Expedition report:
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Your fleet (1 Fighter, 2 Espionage probe) was attacked by an unknown fleet (1 Broodling, 1 Fastling, 3 Scourge, 3 Mudkip, 1 Mutalisk, 3 Guardian, 2 Overlord, 3 Devourer).
You lost the battle. Your entire fleet was destroyed.
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Combat report:
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Enemy fleets met near coordinates [x:x:10]
Debris: 775 metal and 787 minerals

ion_nsk_region got:
0
ion_nsk_region lost 3 points (1 Fighter, 2 Espionage probe)

The battle finished with assaulter`s win
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As you can see, there are debris left after the battle. I suggest to drop these debris around the planets' system. So there could be small debris circles around planets (after battle with pirates/players) and big debris circle around entire planet's system (after battle in expedition).