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They are part of Ten Master Clans, and are from the Sixth Institute, where the research focus was, "Heat Control Magic", it focused greatly on theoretical magic research and lightly on practical military magic research. 
Atsuko, the current Head of the Mutsuzuka Family is an owner of a Geothermal Power Plant Drilling Company.
Area of Influence
The Mutsuzuka Family's influence encompasses specifically the Tōhoku region. During the Master Clans Conference held every four years, the Head of the Mutsuzuka Family gives a report on the status of the region they monitor.
- Family Head : Mutsuzuka Atsuko (六塚 温子)