The hide skill offers a nifty option for missile specialists -- Sniping. Per the rules:
If you’ve already successfully hidden at least 10 feet from your target, you can make one ranged attack, then immediately hide again. You take a -20 penalty on your hide check to conceal yourself after the shot.
The sweet part about sniping is that you are hidden when you attack, which gives you a +2 bonus to hit and denies the defender his dexterity bonus. And if you are a rogue, those magic words "denied his dex bonus" make your sneaky heart go all a-pitter-patter -- rogues gain sneak attack damage against foes who have been denied their dexterity bonus.
All this opens up some interesting play, but that -20 modifier is a killer! How can you optimize your character so that you can successfully snipe at the earliest level possible? Here are my ideas on that.
The basic build: Start with a halfling. That gives you a +1 AC, +1 to hit, +2 Dex ... and, most of all, +4 size modifier to hide. Put as high a stat as you can into Dexterity, and leave a decent 14 or so in Charisma. You don't need any other stat, but extra skills are always nice, so a 12 Int is fine. Remember, your goal is to beat that -20 modifier; with the +2 dex and the size mod, you are already up +5 to hide, oh you halfling.
Eventually you'll be taking a level of shadowdancer, so keep in mind that you need to put ranks in perform as well as move silent and hide. Other skills should include use magic device (UMD), bluff, and the skills you want for your back-up utility (see below). The first three feats you need to take (to meet the shadowdancer prereqs) are Combat Reflexes, Dodge, and Mobility -- yeah, I know it hurts to take feats you won't use much, but the ability to hide in plain sight makes them worth it.
Low levels: Sorry, old pal, but at low levels you just won't be sniping. There's no way to overcome that -20 mod. Your best bet at low levels is to carry around short spears or Alchemist’s Fire and hope to surprise foes. If you do, you'll get sneak attack damage on those thrown attacks (halflings get a +1 throwing), and if you win initiative, you'll still be sneak attacking while foes are flat-footed. Keep pumping ranks into hide and UMD especially.
Middle-low levels: At last you are starting to have what you need to snipe. That Cloak of Elvenkind offers a +5 to hide, so with that, your size, your 18 or more Dex, and your maxed out ranks, by level 5 you should be looking at +21 on hide checks. That puts you at +1 net on hide checks trying to beat opposed spot rolls to remain hidden after firing -- not too good, but you might stay hid versus some opponents some of the time.
Not only that, but with 8 ranks of UMD, a 14 Chr, and a Circlet of Persuasion, your UMD check is a +13. That means you trigger wands with a roll of 7 or better -- not too shabby. If you are feeling cautious, and you want to wait for even better rolls, then stick with the spears and Alchemist’s Fire. But if you feel like taking risks, or at any rate, in a few levels, when your checks are higher, then it's time to take out the wands.
The sweet spot of sniping comes from hitting almost all the time. With a typical archer strategy, you take a -2 hit in order to max out your attacks with Rapid Shot: two per round, three per round, etc. Many of those will not hit, but enough do that it seems worthwhile. But the sniper will never make more than one attack per round. It takes a move action to snipe, so that only leaves you with a standard action to attack with. One attack.
But that's just peachy, since your attack almost never misses. First, you are hiding, so your opponent loses his dex bonus and you get a +2 to hit. Second, per the SRD, "any situation that denies you your Dexterity bonus also denies you dodge bonuses." Third, by using ranged touch attacks instead of regular attacks, your foe gains no bonus from armor or natural armor. Hitting your foe becomes very easy after you take away dex bonuses, dodge bonuses, armor bonuses, and natural armor bonuses!
But how are you making these ranged touch attacks? That's where your UMD comes to the fore. A simple, cheap wand of Acid Splash is all you need! Your ranged touch attack deals 1d3 damage -- plus all the sneak attack d6s you can pile on! At only 375 gp, this is well within your means, even with your circlet and cloak.
In fact, now's the time to start thinking about other wands. A wand of Reduce Person, for example, used at the start of a battle, gives you an extra +4 size mod to hide, an extra +2 dex, and your acid splash still does 1d3 + sneak attack damage! Even at fifth level, your net hide roll is now a +6, and you are getting better at staying hid.
You're biggest problem at this point is the practical matter of finding things to hide behind on a regular basis. You can only snipe if you can hide, and you can only hide if you have concealment or cover. D&D is not like a video game such as NeverWinter Nights, in which you can turn on your stealth skill and just fade into semi-invisibility! No, you need something to hide in or hide behind, so keep your eye on the field of battle. Listen to the DM's flavor text. If he mentions a tapestry, a barrel, a throne, or a table, then move to it and hide behind it. If the enemy is watching, you may have to create a diversion to hide (that's a good reason to max your bluff ranks). Out of doors, trees and bushes can serve you well. Remember that to snipe you have to be 10 feet away from your foe, and to gain sneak attack damage you need to be within 30 feet! If you have darkvision and your foe does not, you might be able to hide in the shadows cast by a torch -- within 20 feet a torch is too bright to hide near; within 20 to 40 feet the shadows are perfect. That's tough to judge, though, since torches carried by people tend to move. But if you are frustrated by inadequate places to hide, just you wait!
Middle-high levels: Your life takes a dramatic change for the better at level 8, when you pick up a level of shadowdancer. Now you *can* hide in plain sight, just like a video game character. No need to worry about finding things to hide behind; you can hide anywhere there's a shadow.
As you get to level 10, that -20 mod is not as daunting any more, either. You've traded your Cloak of Elvenkind for Shadow Armor, giving you a +10 on Hide checks. You may even have splurged for the +15 Greater Shadow Armor. Your dexterity is higher, and, since you have maxed out your hide ranks, your hide check is in the vicinity of 13 ranks +5-9 dex +8 size +10-15 armor ... bringing you to the +36 to +45 range. Even with the -20, that's +16 to +25. Sweet!
Now that you've got the shadowdancer prerequisites out of the way, you can also start to think about new feats. Point Blank Shot and Precise Shot are tempting. Skill Mastery in UMD comes in handy. Quickdraw helps you switch out wands fast.
The final package: A halfling rogue 9 / shadowdancer 1 adventures with a wand of scorching ray in one hand and a wand of reduce person in the other. Boots of striding and springing lets you keep up with the long-leggers in the party. Greater shadow armor gives you a +15 on hide checks. Circlet of persuasion boosts your bluff and UMD checks.
You keep to the shadows, basically hiding all the time as you walk. In the first round of combat, you reduce yourself. Thereafter, you hide in plain sight and snipe with the wand of scorching ray -- that's 4d6 fire damage plus 5d6 sneak attack fire damage once per round. Not too shabby, considering that odds are no one will target the hidden sniper! If you meet something that has magic resistance, switch to the acid splash, which bypasses that. If you meet something that resists fire, dig out the ray of frost wand. You've got it covered.
Plan B: You've got it covered, that is, unless the enemy is a plant, elemental, undead, or other creature immune to sneak attacks. Or a foe with Uncanny Dodge. Or a defender with concealment, such as that provided by obscuring mist or darkness or blur spells -- because you can't sneak attack something when you have a miss chance! So what's your Plan B? How will you make yourself useful when you can't sneak attack?
- You call yourself a rogue, but where are your skills! You already have the Circlet, a decent Chr, plus ranks in bluff and perform. Max out the diplomacy and play the party mouthpiece.
- Or go the route of tradition and pick up search, disable device, and open lock. Every party loves the trap mokey.
- Max out the sleight of hand. Even if you can't sneak attack that vampire, you can still slip through shadows and drop a cross in his pocket.
- Work that UMD! Invest in a wand of Cure Serious Wounds and use it on the party tanks who can fight the plants and elementals, even it you can't. Pumping hit points into the champs on the front line is a good way to save your own neck.
- Snipe less effectively! You can still use that wand of scorching ray. Boo hoo, you don't get to do an extra 5d6 per blast. Cry me a Decanter of Endless Water -- and get firing! (Even creatures immune to sneak attacks can lose their dex bonuses, making it easier to hit them, anyway.)
Troubleshooting: Your DM hates you, or at least does his best to throw a monkey wrench into your tactics. After all, there are as many interpretations of the rules as there are players! What do you do?
If your DM's world does not have a magic shoppe on every corner, it may be hard to keep stocked up on the wands you need. If you are lucky, there's a friendly mage in the party who can help you out. Even if the wizard can't make wands, you can pursue the same strategy with scrolls. Just take the Quickdraw feat so you can draw a new scroll every round.
If your good friend the wizard balks at the time or xp he is wasting on you, you may have only one more choice -- multiclass as a mage. Sorcerer is sweet -- you already have a decent Charisma. Cast your own damn acid splashes, reduce persons, and scorching rays. At a minimum, a level or two may be all it takes, especially if you start writing your own scrolls. You might be tempted to take a few more levels and become an Arcane Trickster. The sucky part about that is you lose a few sneak attack dice taking five or six levels of mage. Tough choices. But if you do become a mage, at least you don't have to go nuts with the UMD any more (unless you love those curing wands).
If your DM rules that the sniping was intended for use with a single ranged attack, not an item activation or spell casting, what then? Buy a wand of (or take levels to cast) the druidic produce flame spell. Keep your flaming hand in your pocket while hiding -- take it out and toss those flames while you are sniping!
And if your DM then counters with fire elemental after fire elemental, then throw in the towel -- or vote with your feet!