A Spirit Fusion is a Secret Art of the Oboro Style where two souls are merged into one, normally serving as a means to save a person's life in an act of self-sacrifice. While the one who performs the Spirit Fusion vanishes, the skills of that person are passed in into the one who receives the Spirit Fusion survives at the cost of his or her memory.
Known Uses of Spirit Fusion
- Oboroya Senjyu uses the Spirit Fusion to save Kisuke's life and grants the youth his full knowledge of the Oboro Style. It is unknown if the third canonical ending to Kisuke's story canceled the event.