AxeMental wrote:So, if a single fighter is fighting two orcs, he can't choose the one he wishes to swing at? I realize thats how the book seems to read, but I don't know any DM that sticks by this. It just seems to be one of those removal of "free will" things that cut against the grain of the game.
In general, yes, that's the case. It's not about free will; it's about which target makes itself available to you.
As we all know, a round is one minute long, and all combatants move and attack constantly during that minute. Human reactions being what they are, it is difficult, if not impossible, to see an opening, decide whether this target is the target you want to hit, and strike before the window of opportunity has passed. And this doesn't even consider the possibility of a friend's body simply getting in the way of your otherwise correctly aimed swing.
To take a much-exaggerated example: consider a cartoon fight where the participants are swirling inside a literal whirlwind. Imagine trying to hit one exact target in that whirlwind. You can't. Now, a melee isn't that bad, but it's bad enough that you have an equal chance of hitting a friend as hitting a foe.
Notice that there is nothing to force your melee from joining a nearby melee. Two groups might split into multiple single combats, or multiple groups of two on one, or any number of combinations. This seems to be the case in the example of combat in the
Dungeon Masters Guide. The DM might even allow multiple melees to be within 1" of each other without combining them. The participants must all respect this division to keep it intact, or else the two groups will merge into a single melee.