[Essence_of_War]

A few sample builds:

Straight (mostly) Swordsage:

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Izumi Nobutsuna
OA Samurai 2/SS18
Other Possibilities:
Rn 2/ SS 18; F 2/ SS 18

The best weapon for the SS is probably the spiked chain and the OA Samurai nabs the Ancestral Daisho ability and a bonus feat. This will allow you to make better use of some of the treasure you find if you can convince your DM to allow you the Spiked Chain as your ancestral daisho. If you’re a two weapon fighter, try a 2 level dip in either fighter or ranger to pick up 2 weapon fighting and other goodies.

Stats/Race

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For a 32 pt buy, I’d try something like this:
Str 10 Dex 16 Con 16 Int 12 Wis 14 Cha 8

But you could probably swap the con and wis if you wanted.

I think human is a very strong choice, but many small races are excellent choices also since the SS doesn’t rely on strength to deal damage. The whisper gnome is EXTREMELY saucy. Most of the Halflings can be excellent choices also, and the Water Halfling, if that racial variant is available, is a particularly good choice.

If you’re playing a small race, I’d swap the 12 in Int with the 10 in Str so you can still carry a haversack full of goodies without difficulty.

Feat Progression

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Feats: (Assuming spiked chain)
1 – Exotic Weapon Prof – Spiked Chain
1 (human) – Weapon Finesse
2 (samurai) – Combat or Evasive Reflexes
3 – Shadow Blade
6 – Improved Initiative
9 – Adaptive Style
12 – Close Quarters Fighting
15 – Imp. Unarmed Strike
18 - Unnerving Calm

If you’re a two weapon fighter (assumed Ranger)
1 – Weapon Finesse
1 (human) – Improved Initiative
1 – Track
2 – Endurance
2 – 2xWeapon Fighting
3 – Shadow Blade
6 – Adaptive Style
9 – Imp 2x. Weapon Fighting
12 – Close Quarters Fighting
15 – 2x Weapon Rend
18 – Grt. 2x Weapon Fighting

I could be convinced to swap the order of Close Quarters Fighting and Adaptive Style in either list as the former is MUCH better before you can afford a ring of freedom of movement.

Maneuver Progression:

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Maneuver Progression (1 = SS Level 1; IL = SS Level + 1):
1 – Moment of Perfect Mind* (DM,1); Sudden Leap* (TC,1); Wolf Fang Strike (TC,1); Shadow Blade Technique (SH,1); Sapphire Nightmare Blade (DM,1); Clinging Shadow Strike (SH,1)
2 – Cloak of Deception* (SH,2)
3- Burning Brand (DW,2)
4- Mind Over Body* (DM,3) drop Shadow Blade Technique for Insightful Strike (DM,3)
5- Shadow Garrote (SH,3)
6- Death From Above* (TC,4) drop Sapphire Nightmare Blade for Ruby Nightmare Blade (DM,4)
7- Obscuring Shadow Veil (SH,4)
8- Dancing Mongoose* (TC,5) drop Clinging Shadow Strike for Shadow Stride* (SH,5)
9- Pouncing Charge* (TC,5)
10- Shadow Noose* (SH,6) drop Wolf Fang Strike for Greater Insightful Strike* (DM,6)
11- Rabid Bear Strike* (TC,6)
12- Swooping Dragon* (TC,7) drop Burning Brand for Shadow Blink* (SH,7)
13- Death in the Dark* (SH,7)
14- Raging Mongoose* (TC,8) drop Ruby Nightmare Blade for Diamond Nightmare Blade* (DM,8)
15-One with the Shadow* (SH,8)
16- Time Stands Still* (DM,9) drop Shadow Garrote for 5-Finger Shadow*… (SH,9)
17- Diamond Defense* (DM,8)
18- Quicksilver Motion (DM,7) drop Obscuring Shadow Veil for Mountain Tombstone Strike* (SD,9)

*’d maneuvers are ones that are part of the final repertoire

Final Maneuvers
1 – Moment of Perfect Mind (DM, Ctr); Sudden Leap (TC,Boost)
2 – Cloak of Deception (SH,Boost)
3 – Mind Over Body (DM, Ctr)
4 – Death from Above (TC, Strike)
5 – Shadow Stride (SH,-); Dancing Mongoose (TC, Boost); Pouncing Charge (TC,Strike)
6 – Greater Insightful Strike (DM,Strike); Rabid Bear Strike (TC, Strike); Shadow Noose (SH,-); Crushing Vice (SD,6)
7 – Shadow Blink (SH,-); Swooping Dragon Strike (TC,Strike); Quicksilver Motion (DM, Boost); Death in the Dark (SH, Strike)
8 – Raging Mongoose (TC, Boost); One with the Shadow (SH, Ctr); Diamond Nightmare Blade (DM,Strike); Diamond Defense (DM,Ctr)
9 – Time Stands Still (DM, Strike); 5-Finger…(SH, Strike); Mountain Tombstone Strike (SD,Strike)

We need to take maximum advantage of the Shadow Blade feat, so expect to stay mostly in Assassin’s Stance once you have access to it.
1 – Hunter’s Sense – Gives Scent, situationally useful. Notable interaction with Track if you’re a ranger also!
1 – Child of Shadow – Mainly to use Shadow Blade
3 – Assassin’s Stance – yay, we’ll spend a lot of time in this one
5 – Hearing the Air – You never know when you might need blindsense and a bonus to listen checks
8 – Balance on the Sky – Probably won’t be using it in combat due to the “one hand free” clause, but can be extremely useful.

Commonly Readied Maneuvers:

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Commonly Readied Maneuvers:
1 – Time Stands Still
2 – 5-Finger Fiasco
3 – Diamond Nightmare Blade
4 – Swooping Dragon Strike
5 – Greater Insightful Strike
6 – Raging Mongoose
7 – Shadow Stride
8 – Shadow Blink
9 – One with the Shadow
10 – Diamond Defense
11 – Mind Over Body

So what do I do with this?

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Have a blast! You've got reach, a number of excellent strikes, several solid boosts and teleportation effects, and a number of useful counters. Between tumble, quicksilver motion and your teleportation abilities you should be able to move around the battlefield more or less at will, and land a devastating strike every round for your standard action! Your job is to let the big scary guys in the party draw the heavy fire while you dance around the battle scoring decisive hits. Alternatively, you make an excellent scout as you're able to defend yourself, stay unnoticed, make quick escapes, and deal decisively with unprepared enemies.

As far as saves go, I would always keep Mind Over Body prepared to dodge poisons and nasty save-or-suck/dies aimed at your fort save. If you know you're going up against magic users, it may be wise to swap one of your strikes to keep Moment of Perfect Mind prepared also to buffer your will save.

Edit: 1 or 2 more coming.