The Angelic Host

At the end of your opponent's turn, you can select a number of Adeptus Astartes Jump Pack units from your army (excluding units that are within Engagement Range of one or more enemy units). The maximum number of units you can select depends on the battle size, as follows:

Incursion - Up to 1 unit Strike Force - Up to 2 units Onslaught - Up to 3 units

Once you have made your selections, remove those units from the battlefield and place them into Strategic Reserves. In the Reinforcements step of your next Movement phase, set each of those units up using their Deep Strike ability.