The Ygwer Code was a universal code of conduct among the magic academies that forbade certain acts. It outlawed a number of acts. One of the preeminent was the killing of living creatures (or poaching certain parts) for the purpose of harvesting magical energy, with the exception of certain plants. The Draol and some other minor orders got around this in use of battlefield mages who harvested energy from slain soldiers killed by non-magical combatants. The illicit arts were also barred, which included attempting to reanimate the dead, resurrection, etc.
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