How good creatures are in close combat depends almost entirely on their physical characteristics, in other words how fast, strong, tough and ferocious they are. Armour remains useful for warding off blows and shots, but ranged weaponry becomes a secondary consideration, the best gun in the galaxy won't help if your opponent is bashing your brains out with a rock!
In close combat, both players' models fight. How many blows are struck and who strikes first is discussed below. The rules are written assuming that there is only a single close combat occurring in the turn. Of course, there may be several separate assaults being fought simultaneously in different parts of the battlefield. If this is the case, the player whose turn it can choose what order to fight the combats in; complete steps 3-7 for each combat before moving on to the next.