Iaijutsu Master (3.5e Optimized Character Build)
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Want to make sure your enemy dies in the first round? Well go first, stab, and then ask questions. This build is reliant on the Iaijutsu Focus skill. Allowing for tons of damage in the first round, although it becomes problematic if they survive after your initial strike.
 Game Rule Components
The Focus ability (Oriental Adventures, 125) grants a +4 insight bonus to Iaijutsu Focus checks, only costs 640gp, and does not count against the weapon's enhancement bonus for purposes of determining weapon cost.
Dust of Immobility (Oriental Adventures, 140) forces opponents to succeed on a Fortitude saving throw or be affected by hold person and only costs 300gp. This allows you additional uses of Iaijutsu Focus against the same opponent.
A Circlet of Persuasion (Dungeon Master's Guide 252) provides a +3 competence bonus to Charisma-based checks (which includes Iaijutsu Focus), and costs 4,500gp.
A Cloak of Charisma (Dungeon Master's Guide 253) provides an enhancement bonus to Charisma which will both help with Iaijutsu Focus checks and add to the bonus damage to Iaijutsu bonus dice at 10th level.
If you can convince your DM to allow it, you could create a Crystal Mask (Magic Item Compendium) that provides a bonus to Iaijutsu Focus. This would be a +10 Insight bonus to Iaijutsu Focus for 10,000gp.
The Build as is, uses as Human as the race, with one flaw. Preferably Shaky, as the -2 to hit with ranged weapons is completely irrelevant to this Build.
|Saving Throws||Feats|| Class
|1st||Swashbuckler||+1||+2||+0||+0||Skill Focus(Iaijutsu Focus), Quick Draw, Dodge||Weapon Finesse||Iaijutsu Focus 4 Ranks|
|2nd||Fighter||+2||+4||+0||+0||—||Weapon Juggle||Iaijutsu Focus 5 Ranks|
|3rd||Fighter||+3||+5||+0||+0||Improved Initiative||Mobility||Iaijutsu Focus 6 Ranks|
|4th||Fighter||+4||+5||+1||+1||—||—||Iaijutsu Focus 7 Ranks|
|5th||Swashbuckler||+5||+6||+1||+1||—||Grace(+1 to Reflex saves)||Iaijutsu Focus 8 Ranks|
|6th||Swashbuckler||+6||+6||+2||+2||Weapon Focus(Katana)||Insightful Strike(Intelligence Modifier to damage rolls when using Weapon Finesse)||Iaijutsu Focus 9 Ranks|
|7th||Iaijutsu Master||+7||+6||+4||+2||—||Weapon Finesse(Katana), Canny Defense||Iaijutsu Focus 10 Ranks|
|8th||Iaijutsu Master||+8||+6||+5||+2||—||Lightning Blade||Iaijutsu Focus 11 Ranks|
|9th||Iaijutsu Master||+9||+7||+5||+3||Improved Critical(Katana)||—||Iaijutsu Focus 12 Ranks|
|10th||Iaijutsu Master||+10||+7||+7||+3||—||Spring Attack||Iaijutsu Focus 13 Ranks|
|11th||Iaijutsu Master||+11||+7||+7||+3||—||Strike From the Void||Iaijutsu Focus 14 Ranks|
|12th||Fighter||+12||+8||+7||+3||Weapon Specialization(Katana)||Exotic Weapon Proficiency(Katana)||Iaijutsu Focus 15 Ranks|
|13th||Fighter||+13||+8||+7||+3||—||—||Iaijutsu Focus 16 Ranks|
|14th||Fighter||+14||+9||+8||+4||—||Power Critical(Katana)||Iaijutsu Focus 17 Ranks|
|15th||Iaijutsu Master||+15||+10||+9||+5||Deflect Arrows||—||Iaijutsu Focus 18 Ranks|
|16th||Iaijutsu Master||+ 16||+10||+9||+5||—||—||Iaijutsu Focus 19 Ranks|
|17th||Iaijutsu Master||+17||+10||+10||+5||—||One Strike, Two Cuts||Iaijutsu Focus 20 Ranks|
|18th||Iaijutsu Master||+18||+11||+10||+6||Greater Weapon Focus(Katana)||Toughness||Iaijutsu Focus 21 Ranks|
|19th||Iaijutsu Master||+19||+11||+11||+6||—||Strike with no Thought||Iaijutsu Focus 22 Ranks|
|20th||Swashbuckler||+20||+12||+11||+6||—||—||Iaijutsu Focus 23 Ranks|
 Side Note
As my gaming group never bothers with Cross Class skills, you may need to take Cross Class Learning(Iaijutsu Focus) to get the full benefit of the skill, and therefore the build.
It is more than likely that you will go first, with both your Charisma and your Dexterity(which should be your high stats!!), as well as Improved Initiative. Therefore allowing you to deal a ton of damage before your opponent gets to think.
With Spring Attack you can move away from your opponent, to get a chance to hide, or go invisible, and attack again.
It is important to note that Iaijutsu focus only functions against Flat-Footed and Immobilized opponents, and that the bonus damage applies to the first attack made after the check. Additionally, however, to gain the benefits of Iaijutsu Focus, you must draw a weapon in the same round, so Quick Draw and Quick Sheath are absolutely necessary to this build. Quick Sheath makes sheathing your weapon a free action, which does not provoke attacks of opportunity, allowing you to freely draw and sheath your weapon throughout combat, conceivably gaining the benefits of Iaijutsu Focus every attack (the check is a free action).
 Munchkin-Size Me
Take a race with high Dexterity, Intelligence, or Charisma with no penalties to any of those attributes. The Dvati from the Dragon Compendium will double the number of attacks per round (+1LA). Templates that are nice: Magic Blooded(+2cha -2wis) and Unseelie Fey(+2dex, +2cha, -2str, -2con, dr15/cold iron and wings), both are 0LA.
Taking a Class that gains Hide in Plain Sight would also help, as you could attack, tumble/hide, and use Iaijutsu Focus again and again.
This class is intended for strictly melee combat, without a trusting ally to help take down flying or ranged combatants, you are in for a world of hurt.
With the poor will save, spells will also be a problem.