making the best Crossbowman

[Better_with_Bacon]

Good evening fellow gamers,

I'm trying to make a crossbowman, with an emphasis on single-hit damage.

Heavy Crossbow is a must.
Feats that let me snipe/remain hidden are a plus
Magical items that increase the damage of each arrow
Race is leaning towards Human or Half elf

But, I am interested in your input.

Very Respectfully,
--Bacon

[Petty Alchemy]

Sounds pretty basic then. Fighter (Crossbowman) with the Vital Strike line of feats (as well as standard archery feats. I guess you can ignore Crossbow Mastery if you want singleshot to be your deal). I don't think you can combine Vital with Focused Shot, which is alright because it's pretty awful.

Halflings are the best snipers because of their alternate racial Swift as Shadows, which reduces the sniping penalty to a mere -10 (in addition to their size advantage). If you want Human or Half-Elf, either is equally good I guess.

So you'll be the best at sniping with single shots this way. Not a very effective fighting tactic unless dueling a spellcaster or playing a solo game, but I assume you have a reason to want this.

[Timebomb]

I'd go with something like a Permanency Enlarged inquisitor wielding an actually large sized repeating crossbow (I value being able to make an attack every turn over more damage, though you could carry a couple heavies I guess) with a ring of spell knowledge I (gravity bow), Vital Strike, using fire bolts. This'll get you 4d8+2d4 (maybe 1d4 depending on if fire bolts count as "weapon damage dice") before weapon magic or non-vital strike feats at level 8. With a potential +2 damage from Judgement.

You'll want the standard archery feats (point blank shot, precise shot, ect), Bracers of the Falcon, the largest bonus magic weapon you can, and maybe some specialty arrows to break out in a pinch.

Inquisitor gets stealth as a class skill, dex is your main stat, and you get 6+int skills. You'll be good at stealth.

[CWheezy]

The crossbow archetype is actually worse than a regular fighter, so that sucks.

Here is an example guy:

Halfling Dude:

Unnamed Hero
Halfling Fighter 10
CG Small humanoid (halfling)
Init +12; Senses Perception +9
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Defense
--------------------
AC 24, touch 18, flat-footed 19 (+6 armor, +5 Dex, +1 size, +2 deflection)
hp 94 (10d10+30)
Fort +12, Ref +12, Will +8 (+3 vs. fear); +4 vs. effects that cause you to lose your grip on weapons, +2 vs. fear
Defensive Abilities bravery +3
--------------------
Offense
--------------------
Speed 20 ft.
Melee masterwork heavy pick +13/+8 (1d4+1/×4)
Ranged +3 double crossbow +15/+15/+10 (1d6+13/19-20)
Special Attacks weapon trainings (heavy blades +3, crossbows +4)
--------------------
Statistics
--------------------
Str 13, Dex 22, Con 14, Int 10, Wis 14, Cha 9
Base Atk +10; CMB +10; CMD 28 (32 vs. disarm, 32 vs. sunder)
Feats Crossbow Mastery, Deadly Aim, Devastating Strike, Exotic Weapon Proficiency (double crossbow), Improved Initiative, Point-Blank Shot, Precise Shot, Rapid Reload, Rapid Shot, Skill Focus (Stealth), Vital Strike
Traits bandit (river kingdoms), reactionary
Skills Acrobatics +8 (+4 jump), Climb +4, Perception +9, Stealth +34, Swim +4; Racial Modifiers +2 Perception, swift as shadows
Languages Common, Halfling
SQ armor training 2
Other Gear masterwork breastplate, +3 double crossbow, masterwork heavy pick, belt of physical might (dex & con +2), cloak of resistance +2, gloves of dueling, ring of protection +2, stalker's mask, 150 gp
--------------------
Special Abilities
--------------------
Bandit (River Kingdoms) (Stealth) +1 to Stealth checks, Stealth is always a class skill for you.
Bravery +3 (Ex) +3 to Will save vs. Fear
Crossbow Mastery (Double crossbow) You can reload any crossbow as a free action. With your chosen crossbow type, this does not provoke attacks of opportunity.
Deadly Aim -3/+6 Trade a penalty to ranged attacks for a bonus to ranged damage.
Devastating Strike Deal extra damage when using Vital Strike bonus
Fearless +2 racial bonus vs Fear saves.
Gloves of dueling These supple gloves grant the wearer a +4 bonus to her CMD against disarm attacks, attempts to sunder her wielded weapons, and effects that cause her to lose her grip on her weapons (such as grease). The wearer doesn't drop held weapons when panicked or stunned. If the wearer has the weapon training class feature and is using an appropriate weapon, her weapon training bonus increases by +2.

Construction
Requirements Craft Wondrous Item, greater magic weapon; Cost 7,500 gp
Point-Blank Shot +1 to attack and damage rolls with ranged weapons at up to 30 feet.
Precise Shot You don't get -4 to hit when shooting or throwing into melee.
Rapid Reload (Double crossbow) You can reload fast with one type of Crossbow or Firearm.
Rapid Shot You get an extra attack with ranged weapons. Each attack is at -2.
Stalker's mask (1/day) Take the face of one target in 60 ft, +10 to disguise as them, +2 to weapon att/dam vs them.
Swift as Shadows Reduce the penalty for Stealth while moving by 5 and reduce the penalty for sniping by 10.
Vital Strike Standard action: x2 weapon damage dice.
Weapon Training (Blades, Heavy) +3 (Ex) +3 Attack, Damage, CMB, CMD with Heavy Blades
Weapon Training (Crossbows) +4 (Ex) +4 Attack, Damage, CMB, CMD with Crossbows

So, I did my best.

When he hits a guy, he has +24 to re-stealth, which is ok. When you snipe, you fire both bolts with +15 to hit, and each bolt does 2d6+15, which is not so bad, but you will need a minimum of 2 stealth checks to kill a dude, assuming all 4 bolts hit, which may not be true.

You are pretty damn stealthy though

[sgriobhadair]

To get the best out of a single shot, maybe consider poisons.

[haruhiko88]

We have one of these types in the Skull & Shackles game I run, he is a dwarven crossbow wielding sniper/pirate hunter. He is a Fighter (crossbowman) 4/Ranger (no archetype) 1 at the moment and while his damage was slow to start it will start piling up soon. In short range he uses multiple attacks with crossbow mastery, but when the ship is closing in on another ship he sits in the crows nest, next level at 2 ranger I'm adding bulls eye shot and prone shooter to the rangers bonus feats for the crossbow style he'll be taking bulls eye shot and taking aim every turn. At 7 vital strike for more damage.

[maouse]

Heavy Crossbow? Why not oversized Minotaur Dual Crossbow? Just asking...

[Oterisk]

If you want to do a one shot crossbow build, you'll want to consider the Alchemist, particularly the Mindchemist Archetype for extra Intelligence, since it'll be your greatest damage booster. The Explosive missile discovery allows you to add your Bomb damage to your shot. It's a standard action, so no adding vital strike, but you can add Targeted Bomb Admixture to double your intelligence on the damage. This does work with Kirin Strike as well, so you can actually add 4x your intelligence to damage with one hit (you just have to use 2 swift actions before you can do that, Kirin strike is a little lame like that) so you don't need to make it a priority.

9th level build, Human Mindchemist 20 pt buy. This build uses a light crossbow because it'll save you the rapid reload feat.

10, 18, 12, 24(28alc), 10, 8 (+2 belt dex, +4 headband Int should be doable)

Feats: 1 Point Blank Shot, Precise shot, 3 Deadly Aim, 5 Improved Unarmed Strike, 7 Kirin Style, 9 Kirin Strike
Discoveries: 2 Tanglefoot Bomb, 4 Explosive Missile, 6 Frost Bomb, 8 Force Bombs

Having the time to prebuff makes you really amazing but you should be capable in a fight that you don't expect as well. Your Cognatogen boosts your Int for tens of minutes, so it will last most one day dungeons.

In a Fight, on the first round of battle you should initiate Kirin Style and do a minor buff. Reduce person is good for defense, to hit and stealth, but we're focusing on damage: Targeted Bomb Admixture. Then on the second round let off a shot for 1d8+5d6+18 or 40 average damage. Start with a frost bomb or Tanglefoot bomb depending on your opponent with a DC 23 Reflex to avoid the Staggering or Entagled conditions. Either one helps your ability to hit them with another shot. On the third round, you'll do 58 average with Kirin style. Crits will do an additional 1d8+1d6+9 (17 average) or so, since you are really hitting with two weapons at the same time. I'd pick up improved crit at level 11.

If you get the chance to prebuff, Reduce person and Invisibility are good so you will have a +29 to stealth without investing skill ranks, which you could do if you liked. If you root someone with Tanglefoot, you can instead Vomit Swarm on them for some nastiness.

You'll also get all the perks of being an alchemist, extracts for things like Invisibility and Fly, and you also get double your Intelligence bonus to all knowledge checks which puts Bards to shame on the knowledge monkey front.

[Imbicatus]

Kobold is actually a great race for the Crossbowman, as they have a bonus to Dex and the alternate FCB to give you +1/2 Damage vs targets denied Dex to AC. Improved Deadshot denies Dex to AC. It's also worthwhile to multiclass into Rogue after level 7, as Improved Deadshot also allows any ready to be a sneak attack.

This will never do as much damage as a full attacking Archer, but it will give a very big hit, and will murder enemy spellcasters.