@Riot How complicated would the Ruined King be to create?

Besides the kit having to be entirely unique, the Ruined King has been mentioned several times before and seemingly known to nearly all champions that have an affiliation to the Isles. Would certain champions need a small VO rework in reaction to his presence like Yorick and Kindred who seem to harbor some sort of strong distaste for him? Would the Ruined King himself be incredibly powerful yet immensely difficult to comprehend and control? Some input would be nice.