[@VitaVitaAR]

Again the leylines wouldn't even sustain such a place because mystery would be dying. The only way this even works is if fusang is as a result of a grail wish and is thus exists in a space that is so choked full of mystery that anything occuring inside of it works independently.

Command seals function as absolutes, not even Gilgamesh can resist them, the only reason one wouldn't use a command seal on gilgamesh is once that command is carried out, gilgamesh would murder you immediately after due to his ego. However even Saber who showed a strong will, was still forced to destroy the Grail, the entire thing she strived for. So Command seals can force a servant to go against their own will and deploy an NP.

[i]Who watchs the watchmen[/i]
When you have servants policing themselves, at what point do the masters become irreverent as anything more then cattle, since its obvious at that point the only thing stopping servants is other servants. At which point is it ethical to even have command seals in that society.

to answer the last one
And technically the way to start an arms race against servants is to set up your own servant summoning method. Which eventaully makes fusang wholly irrelevent as a hub of servants.


Though there is a really easy response to this and that is to say Fusang isn't the only place where servants are, but it is the only place where they are allowed to roam freely due to its remoteness. Because anywhere else would have massive restrictions on servants. But I wouldn't find it strange if servants were allowed small trips to their homeland on good behavior (evil aligned servants aren't allowed to leave fusang for instance)

(and of course we'll just ignore mystery as a sort of stopgap measure to handwave the world knowing)

Im just trying to wrap my head around Fusangs place on a global level that is all.