It targets the nearest target. At the time I didn't even realize that the function/key named "Target Nearest Enemy" was supposed to target something else if an enemy was already targeted, and that caused me a lot of trouble, which this macro would of course aliviate. Really, I would preffer separate nearest and next enemy keys, but most of the time, I either want the actual nearest target, or the target of one of my party members, else I'm inclined to just use mouse selection.