Wood (林, hayashi) is weak against fire and is strong against wind. The wood element includes other elements such as music, energy, space, darkness. Most wood users have a different range of hissatsu techniques with different elements.
Void (無, mu) has no weaknesses and isn't strong against other elements. This element includes darkness or hissatsu that can have two or more elements, such as Fuurinkazan Destroyer, which includes the four elements. There are no void characters, only hissatsu, keshin and souls.
- List of all void hissatsu: Void Hissatsu