Seal of Oath

At the start of the first battle round, before the first turn begins, select one enemy unit. Until the end of the battle, the bearer has the following ability: ‘Seal of Oath (Aura): While a friendly Ultramarines Core or Ultramarines Character unit is within 6" of the bearer, each time a model in that unit makes an attack against the enemy unit you selected at the start of the first battle round, you can re-roll that attack’s hit roll and you can re-roll that attack’s wound roll.