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Are you sure some "Rutileans" didn't come to the Belathre Magic Academy? (Will think of a better name at some point)
Maybe one day, but for now Rutileo is just beginning to talk with other Kingdoms.
It is the first time in a long time it has been able to,
Due to wars within it's kingdom. Now there is peace, Rutileo can finally expand.

I can imagine a champion that is taken with much effort (at the expense of 3 of a kingdom's finest knights) will not be handed back over lightly for just a ransom, if the threat of ar still exists (even if there is a current cease fire) Only in exchange for some of their own men maybe, but not for any amount of money. Maybe it should say that these kind of prisoners can only be exchanged for other men (of equal value) as part of a peace treaty.
Just some thoughts.
That is how chivalry worked in the Medieval ages...

And in the same scenarios.
It was just: the way things worked, their way of life.
If the other side had captured some of your sides men,
then yes there were also prisoner exchanges.
