Unarmed Strike is probably the most versatile and most useful of melee weapons in D&D. With enough creativity, unarmed strikes can do more damage than any other melee weapons, achieve similar applications of reach, and reach unparalleled levels of versatility. To stick unarmed strikes as a monk-only weapon, or simply a cute trick makes the practical optimizer in me cry. Here I hope to show you just a little bit of the amazing versatility that unarmed strikes can bring your martial characters.
Two-Weapon FightingProbably the most straight-forward and awesome application of unarmed strikes is their role in two-weapon fighting. Since you can execute unarmed strikes with kicks, knees, elbows, and such, you can have an extra hand free. For martial characters, extra hands are
rather important. There are myriad uses for a free hand while two-weapon fighting, but two really jump out at me for a martial character.
The first, is that you can wield a shield in your off-hand. You know, those things we're supposed to stay away from because two-weapon fighting or two-handed fighting are better than extra AC? Now we can have our cake and eat it too, because our off-hand weapon is a swift kick in the face following up our longsword.
The second option that stick out for me is rather more exciting. With unarmed strikes as our off-hand weapon, we can wield a two-handed weapon as our primary weapon in a TWF full-attack. That means we can use those juicy 1d10, 1d12, and 2d6 weapons with the even more important feature of 1.5xSTR to damage. Completely ignoring whatever damage we've achieved for our unarmed strike, a two-weapon routine now looks like 1.5xSTR and 0.5xSTR for 2xSTR overall, versus 1xSTR and 0.5xSTR for 1.5xSTR overall for the typical two-weapon loadout.
Oh, and if you picked up the unarmed strike ability of a monk or unarmed swordsage? They do 1xSTR with ALL unarmed strikes, because they never have an off-hand for unarmed strikes. So now using a shield still gives you more damage then typical TWF, due to full strength with the off-weapon. The two-handed weapon and unarmed strike TWF routine does a total of
2.5xSTR total to its damage. That is your strength modifier to damage AGAIN over the typical one-handed weapon plus light weapon TWF routine, and that is still before you look at the increased weapon die sizes from using a two-handed weapon and the infinitely-enhancable unarmed strike.
Monk/Unarmed Swordsage unarmed strikes take no penalty for being designated as off-hand. So you're also being more accurate with using unarmed strikes as off-hand weapons opposed to normal light weapons. Gloves of the Balanced Hand mean that you never have to go without the Two-Weapon Fighting feat, but in a pinch you don't really need it (until you could use improved two-weapon fighting). Without the feat you'll go -4 for the primary weapon and no penalty for the unarmed strike.
Threatened SquaresMost of us realize that spiked gauntlets are a very good thing to have on our martial (and ranged) characters to threaten melee. But you still need a free hand to use a spiked gauntlet. If you have improved unarmed strike, then you always have a melee weapon to threaten the immediate surrounding squares, and no hands need to be free. Smart archers and polearm wielders know that they can adjust their grip to hold their primary weapon in a single hand instantly if they need to deliver gauntlet justice, but there are situations where you won't have gauntlets, or you don't have the freedom to temporarily relinquish your grip. This is admittedly situational, but the smart warrior is always ready, and covers as many contingencies as possible. Do not underestimate the versatility of being able to lay down the hurt hands-free. No need to drop wands/unconscious allies/chests/quest items/throwing weapons/staves/rods/wondrous items/instruments/banners/etc., or let go of levers/ledges/ropes/triggers/buttons/portcullises/trapdoors/etc. This can save you move actions and a LOT of headaches.
PreparednessIf you don't have quick draw or your weapons already drawn, and you're ambushed, you could be in trouble. Drawing a weapon is a move action, or a free action
as part of a move action if your BaB is +1 or higher. If someone is in your face before you have the opportunity to act, you can be in trouble, because they are in position to full-attack you and you still need to use a move action anyways to draw your weapons. With improved unarmed strike, you have a weapon always drawn and ready. This lets you full-attack adjacent opponents in the first round of combat, or allows you to use a standard-action attack before using a move action to move away and drop your weapon. Again, it isn't every day that your opponent is able to get close to you before you can act, but smart adventuring is all about being able to survive every circumstance.
Touch SpellsGishes aren't too common, and usually gishes are enhancing their combat abilities rather than throwing around damage-dealing spells. But it is worth mentioning that in the same standard action as casting a touch-range spell, you can move that touch attack to a normal attack with your unarmed strike, delivering the spell and doing unarmed strike damage. Not applicable all of the time, but it can be a nice way to keep the pressure on your opponent (and activate things like stunning fist.) Try readying an action to strike a threatened caster to force a concentration check with an otherwise non-damaging touch spell.
ConclusionI didn't seek to make a guide for unarmed strikes, as my attention span is limited and a wealth of information is scattered around different handbooks, but I thought it was worth it to consolidate this info in a cogent post. I dunno about the rest of you, but when I use practical optimization in my melee characters, I almost always make room for unarmed strikes. With monk and unarmed swordsage dips, and a few magical items giving easy access, and two-weapon fighting trivially easy to aquire via Gloves of the Balanced Hand, my characters become more flavourful, versatile, memorable, and powerful.
Plus, legitimately beign able to use shields without forking out the big bucks makes me happy
Cheers.