>>53949285>X has nothing to do with Y typeListen retard, when you make a pokemon, you choose the types, it will have to do something with the type, if it has the fucking type.
There is no real reason Skuntank, Greninja and Mabosstiff have the dark type other than the creators wanting them to be a dark type. Any explanation you may come up with justifying their dark type, will likely be applied to other non-dark types that have similar concepts. Something as vague as Luxray being a fierce predator and being nocturnal is enough of a justification for a possible Dark type.
There is no reasonable explanation to why morpeko is a dark type and primeape, gyarados and granbull aren't, since the theme of violence and anger is also used.