Blood Sorcerer( Oriental Adventures, p. 61)
You are descended from Yogo, the Scorpion shugenja who was the first guardian of the Black Scrolls of Fu Leng.
Add +3 to the Difficulty Class of all maho-tsukai spells you cast. However, you also add +3 to the DC for the Fortitude save you must make to avoid accumulating Taint when you cast maho spells.
This feat is only available if the maho-tsukai prestige class, described in Chapter 12: The Shadowlands, is available.