A weapon engraved with the Rune of Smiting causes not 1 but D6 wounds when it wounds its target. Roll to hit and to wound as normal. If the target is wounded then roll a further Do to establish how many wounds are inflicted. Separate saving throws must be made for each wound suffered. Bear in mind that each attack can only be directed against one enemy model, so all D6 wounds from that blow will be suffered by one model and any excess wounds are effectively wasted.