Its complicated. He has said that there are either 10 or 30 magic systems "depending on how you look at it". My interpretation of this is that each Surge, such as Gravity or Transformation, constitutes its own magic system under the "10-definition". The "30-definition" triples the number by splitting each Surge into three, depending on how it is accessed, i.e. Surgebinding/Voidbinding/Fabrials. Now Voidbinding is intuitively related to Odium yes, however the other two are not so clear. Surgebinding is often described as an Honor-based system but there are strong points towards it being a joint Honor/Cultivation system. Then again fabrials could make sense as a Cultivation-based system.