Most Giants carry a big club, often a tree trunk or a big bone. If they have no weapon they will use their enormous fists. The Giant picks one model as his target and brings down his club with a single mighty stroke.
The target may attempt to avoid the blow by taking and passing an Initiative test (use the lowest if the model has several different values). If avoided there is no effect. If failed the target is struck and takes 2D6 wounds with no armour save allowed. If a double is rolled the Giant's club embeds itself in the ground and the Giant cannot attack at all in the following round whilst he recovers his weapon (this ceases to apply if the combat ends before the next round).