User blog comment:Wildoneshelper/My reasons to put "artillery", "cavalry" categories into units riding elephants/@comment-127769-20140205140221/@comment-3225604-20140206032232

At least we include the category from the multipliers, because it is the official data. You may also consider adding the features of the unit also. Therefore, we only have 2-3 additional categories for that unit, that means you won't have more than 10 categories for that unit!