In the new tenth edition of Warhammer 40,000 rules, the Imperial Knights Faction has an Army Rule called Code Chivalric. One of the abilities this allows is called Lay Low The Tyrant. Its description reads: “Each time this model is selected to shoot or fight, re-roll a Hit roll of 1 and re-roll a Wound roll of 1.”
There has been some conflict over how to interpret this. The critical wording seems to be around “…selected to shoot.” Some read it as the model being selected every time it fires any weapon. Others see it as selecting the model once to shoot all its weapons.
But if you look at the core rules, on page 19 there is a sidebar detailing the sequence of a unit during the Shooting phase.
As you can see, the first step is “select eligible unit.” And the third step says “make ranged attacks.” Based on a reading of this sequence it sure seems like you select the unit once, in sequence step 1, and make all ranged attacks with it in sequence step 3.
Clearing the matter up, a Senior Manager for Organized Play at Games Workshop has apparently responded to a US Open organizer’s query about this, stating, “Lay Low The Tyrant will be played as a single hit roll of one and a single wound roll of one at Tacoma.” This was revealed in a screenshot posted to the Knight Households: Imperial Mechanicus, and Chaos Facebook page.