Im glad you like the idea! anyway if i would ever run a defensive set for kyurem-b it should be a special defense set to abuse of its resistances fo grass, eletric and water, max defense doesnt make so much sense to me, its not like kyurem can tank so many phisical hits. Honestly my set was a max hp one, adamant nature, enough speed to outspeed adamant dragonite and the rest in atk. The item should be obviously leftovers, life orb just negates you a cool recovery to do less substitute and the power up isnt really important since you already have 400 or more atk.