The Horiuchi family was formed late in the history of the Unicorn, but the shugenja school bears their name in modern times has an ancient history with roots from before the Great Clan's return to their ancestral home in Rokugan. During their travels outside the borders of the Emerald Empire, the Unicorn discovered many different methods and styles of magic among both their allies and enemies, incorporating them into a single method. After the Horiuchi family was formed they became some of the foremost practitioners of the meishodo method and in modern times the school bears the Horiuchi name.
The original gaijin sorcerers who created name magic could not speak to the elemental kami and had no direct access to the gods. Instead, they forged amulets of power that could simulate magical effects by invoking the true names of the elements. When the Unicorn studied this magic, they realized it trapped a kami into the item, forcing it to reproduce a single effect whenever the sorcerer focused his will into it. The Unicorn changed and adapted the process to fit their own beliefs. Their meishodo amulets no longer trap the kami, but instead appeal to the elements surrounding the amulet to perform the desired magical effects. However, somewhat like the gaijin originals, a Unicorn meishodo amulet contains only one unalterable effect that can be invoked in this manner.
Meishodo is a Unicorn secret, jealously guarded by all of the clan. Meishodo sacrifices power for speed, using a brief incantation rather than an extended dialogue with the kami, and speed has always been an important aspect of the unicorn approach to life.