There’s no need to have wars just over a bit of land and power, but it’ll always happen in this world because there’s people filled with greed and hunger, it’s the same for the immortals, and if no one does anything about it, then the greedy ones will conquer.. hence why good immortals won’t kill each other I guess. plus it’s a rule, whoever founded the rules or ways of chivalry must of had a reason for it.