Winds of the Warp

Use this Stratagem in your opponent's Shooting
phase, when a Traitoris Astartes Biker or Traitoris
Astartes Jump Pack unit from your army that
Advanced in your previous Movement phase,
or that was set up on the battlefield during the
Reinforcements step of your previous Movement
phase, is selected as the target of a ranged attack.
Until the end of the phase, each time an attack is
made against that unit, subtract 1 from that
attack's hit roll.