Add a cloaking nebula with higher cloak than detectable (5 ?) I dont know if this is possible for small nebulas but if possible you could forego all the asteroid fields etc and just have that cloak.
Can't use a nebula, it would cloak the entire system. All in all I'm not too worried about a player attacking the ref but the AI might if we lose a player.
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This is the 21st century, right? Then where the hell is my flying car?
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Assume you have a 1kg squirrel
E=mc^2
E=1kg(3x10^8m/s)^2=9x10^16J
which, if I'm not mistaken, is equivilent to roughly a 50 megaton nuclear bomb.
Fear the squirrel.