This spell is, to the best of anyone’s knowledge, known only to two people : Iuchiban and Yajinden. They have guarded its secrets carefully and so far no other maho-tsukai has ever exhibited its power. The spell allows the caster to literally "leap" his soul into the body of another person within range, instantly and permanently taking their body as his own. The caster must succeed in a Contested Willpower roll against the victim, and if the victim wins, the caster is hurled back into his current body. (The victim will be very much aware that he just fought off some kind of terrible all-consuming power.) The spell does not normally cause the souls to "switch": the abandoned body simply falls dead. The fate of the original soul is unknown, and some Rokugani believe it may actually be destroyed, a truly horrific and blasphemous act. There are some reports of powerful Lost or maho-tsukai being able to switch into the other body rather than be destroyed, but these tales are not confirmed.
The occupied body retains its physical Traits and physical Advantages and Disadvantages, but instantly acquires the mental Traits and Void of the caster, along with all of the caster’s Skills and any Mental or Spiritual Advantages and Disadvantages the caster may have. (Social Advantages or Disadvantages may or may not persist ; the GM should adjudicate such situations.) If the maho-tsukai remains within the same body for an extended period of time (six months or more) it will gradually change to physically resemble the caster’s original physical form,changing Rings, Traits, and Advantages as appropriate.