It’s a big floating hill with palaces built all over it, with a handful of bridges tethering it to the ground far below. The slums in its shadow house a couple of hundred thousand people–not millions, but still a lot more than many MCs will want to pulverize. The slum dwellers are also mostly drudges and the free urban poor rather than soldiers, Alastors, or other obvious targets of the rebellion (a couple thousand of whom do live mostly on the Floating Palace, but still, proportionality).
Ha! While this won’t happen in the game, I’d totally read a fanfic of that. 