Long-distance Communication (遠話 Enwa ), as the name suggests, is the Unrestricted Spell used for communication over a large distance. It has been known to be used during the Great War by the Flame Haze Army. However, the spell is somewhat more complicated than Seal or Humanize; only the few people who are deemed as Unrestricted Spell Masters could use the spell during the war.
Despite its advantages, the spell has a crucial flaw: the spell user cannot specify the target of conversation, resulting in confusion (or "lines crossed") when numerous users cast the spell at the same time. Moreover, communications between continents is also impossible. Ever since modern communications like telegrams and telephones have flourished, the spell is rarely used. Still, long-distant communication is considered useful when fights occur under the Seal. With the Seal activated, every means of communication built by humans stop functioning, leaving Unrestricted Spells as the only way to convey an order from commanders.