Funny things seem to happen with those free facs; I suppose that the game is flawed

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I have seen all sorts of variations, both bad and good (like capturing a Yang base where the Perim had been destroyed and unexpectedly getting a new undeserved one). Most recently, playing as the Blue Meanie, I conquered a Spartan Base, getting it without a Perim (grrr) and proceeded to start building my own as I was feeling paranoid; the next turn, I magically had the Perim after all.