If «Blood Death Knight»: Dancing Rune Weapon; otherwise: Pillar of Frost empowers your next If «Blood Death Knight»: Marrowrend; otherwise: Obliterate to become Reaper's Mark. Reaper's Mark Viciously slice into the soul of your enemy, dealing 81 Shadowfrost damage and applying Reaper's Mark. Each time you deal Shadow or Frost damage, add a stack of Reaper's Mark. After 12 sec or reaching 40 stacks, the mark explodes, dealing 10 damage per stack. Reaper's Mark travels to an unmarked enemy nearby if the target dies. If «Frost Death Knight»: Does not benefit from Killing Machine