Thoughts Triggered by War Magic

Wizet's belief that war magic had not truly been eradicated, but merely restricted from being spread under the term "war magic," also stemmed from his study of two ancient Runes texts.

"War magic" was, of course, magic best suited for war. Using that thought as his starting point, Wizet combined the knowledge recorded in the ancient Runes texts and looked at the magic he had mastered from another angle...

Dumbledore had developed a use for the Patronus Charm that allowed messages to be conveyed through a corporeal Patronus, making it a highly practical means of communication;

Dark wizards were often unable to cast the Patronus Charm. Using it for communication could avoid dark wizards' interference with information and ensure the accuracy of the messages being conveyed.

Correspondingly, Voldemort and the Death Eaters also had a means of communication—the Dark Mark;

The Dark Mark was not merely a symbol of the Death Eaters. Death Eaters could also use it to contact Voldemort;

Voldemort could likewise use the Dark Mark to sense a Death Eater's location or summon Death Eaters through it;

These characteristics of the Dark Mark could also make wartime communication swift and effective.

The two methods of communication emphasized different things. The Death Eaters' actions mainly revolved around killing and destruction, building authority through violence, so the Dark Mark emphasized rapid response and instant communication;

Communication through the Patronus Charm, meanwhile, could not only convey the caster's words, but even use a corporeal Patronus to deliver objects. Its emphasis lay in the diversity of what could be conveyed.

Communication was an extremely crucial part of war. Whether messages were delivered through the Patronus Charm or contact was established through the Dark Mark, both could in fact be considered war magic.

Following this line of thought, there were many more