If Warden was supposed to be for 'dark' champions and Marauder for 'light'...
Why is Karma a Warden and Olaf a Marauder? I can see Jax (most of his skins are darker) and Alistar (kinda), but I thought the justification for Warden Sivir and Marauder Ashe was that the skins team wanted to do something 'new' with those champs, IE a darker skin for Ashe and a lighter skin for Sivir.
Karma's skins are generally light (order of the lotus, sun goddess) and Olaf's skins are darker (bar Brolaf). This seems like just another skin for those two.