Pirates

Nine pirate factions live in the world. Each one starts a new game with a random hoard of gold, regions and units. After that, it grows only by what it steals, so the factions that nobody fights become the dangerous ones.

Pirates raid players at random. A raid is not a battle, so a weak faction can still rob you. Each raid carries off one kind of thing: your troopers, jets, turrets, tanks, agents, or gold, about a thirtieth of it. They never take bombers, carriers, or your regions. The raid also gives the faction new regions, so a pirate that just robbed someone holds more regions.

You can attack a faction to take goods back. A win returns a third of its gold, regions, agents and troopers, and a quarter of its jets, turrets and tanks. One raid often recovers what a faction took from you; two or three will if it is fat. Attacking costs you casualties whether you win or lose, so do not raid a faction that holds nothing.

Listing military on the Trading Market does not hide it from pirates, but it does help some: your camp is raided about twice as often as your listing.

Tip: a faction that you keep beaten stays weak, because it gets new units only by stealing them. Big realms are raided more often than small ones.