Demolition Run: Once per battle round, after this unit ends a Normal move, you can select one enemy unit within 6" of and visible to this unit and roll one D6 for each model in this unit: for each 4+, that enemy unit suffers 1 mortal wound.
You 100% cannot use Demolition Run multiple times in a Turn. This is an change from the original rule and is noted as such in the Index Card Errata document.