Ok, so this is a 3.5 arcane trickster sneak attack smackdown. I wanted to make an assassin type character who isn't reliant on anyone else for his combos, and can pull off the attack once a day without using any consumable resources (no potions/scrolls/etc.) This is also similar to a couple of existing smacks, but I wanted to update it to 3.5 using almost all SRD material (the polymorph form is from the MM2). This isn't as impressive damage wise as some of the smacks I've seen, but does break the smackdown barrier. I plan on using him as an NPC assassin if a player manages to really piss off someone who could afford this guy.
So, the character:
Tiefling Rogue 3/Wizard 5/Arcane Trickster 7 (ECL 16) (28pt buy)
(notes: Tiefling is important to get the outsider type, so that you can use polymorph to assume other outsider forms.)
Str 10
Dex 14 +2 racial +1 inherent +1 level = 18
Con 15 +1 level = 16
Int 15+2 racial+1 level+6 enhancement = 24
Wis 10
Cha 10 - 2 racial = 8
Average HP: 88
Spells/day: 6/6/6/5/4/4/3
Sneak Attack: 5d6
Feats: Two weapon fighting, Improved two weapon fighting, Quick draw, any three you want to round out the character
Saves: Fort +13/Ref +19/Will +15
Skills: 140 points
Equipment
2 +1 short swords of Spell Storing (16,620 gp)
Amulet of Natural Armor +3 (18,000gp)
Headband of Intellect +4 (16,000gp)
Tome of Quickness of Action +1 (27,500gp)
Boots of Speed (12,000 gp)
Pale Green Ioun Stone (30,000 gp) (+1 competence attacks/save/skills/ability checks)
Ring of Protection +3 (18,000 gp)
Rod of Quickening (75,500 gp)
Cloak of Resistance +4 (16,000)
Total: 229,620 gp
Previous Preparation
Greater Magic Weapon on both short swords
Mage Armor on self
Contingent Polymorph:Kelvezu with the casting of Transformation as the trigger.
Nondetection
Surprise Round:
Cast Greater Invisibility
Cast quickened Disintegrate - ranged touch +11 24d6+5d6 sneak attack (Avg 101.5)
Next Round:
Activate Boots of Speed - Free Action
Cast quickened Transformation - Free Action
Contingent Polymorph:Kelvezu (Assassin Demons from MM2) goes off - Free Action
Drop Rod of Quickening - Free Action
New Stats
Str: 24 Dex 36 Con: 20
Average HP: 118
AC: 10, +18 Natural, +13 Dex, +3 Deflection, +4 Armor, +1 Haste = 49
Saves: Fort +15/Ref +28/Will +15
Sneak Attack: 13d6
Attack Bonus: BAB +15, Dex +13, Two Weapon -2, Haste +1, Enhancement +3, Competence +1 = +31
Full Attack : +31/+31/+31/+26/+26/+21
+31 1d6+10+13d6+6d6(vampiric touch)
+31 1d6+6+13d6+6d6(vampiric touch)
+31 1d6+10+13d6
+26 1d6+10+13d6
+26 1d6+6+13d6
+21 1d6+10+13d6
If everything hits, thats 96d6+52, or an average of 388 damage, with an average of 21 temporary hit points gained (assuming temp hit points dont stack). Maximum damage is 628.
After the first round, provided he can keep up sneak attacks (probably by invisibility) the damage drops to 84d6+26, or an average of 310 damage a round. Even if he only hits with his primary three attacks, thats 215 damage in the first round, dropping to 173 per round afterwards. And he can keep this up for ten rounds.
Depending on how the Kelvezu poison ability works on their weapons (whether or not it happens automatically), there's also a DC 22 Fort save for 1d6 con damage with each hit. Also depending on how the ruling goes on the gaining subtype clause of polymorph, you may get immunity to poison and electricity, acid/cold/fire resistance 10, and telepathy.
The character is somewhat weak on hit points, but has a great AC and decent saves, plus full concealment. He's also used a large portion of his spell power to pull this off, but still has all his 5th level spells, and a decent selection of lower level spells to use. If you want to do more damage, you can swap out the ioun stone and get the wounding ability added to each short sword for an additional possible six Constitution damage each round (this makes total equipment cost 247,620).
This strategy is totally useless against creatures immune to sneak attack, in which case he's better off throwing blasting spells - scorching ray, cone of cold, etc. The rod of quickening helps him in a spell assault as well, though he probably won't break the smack barrier. But with sufficient information (which he should be able to get through divinations), he can tailor his assault to his target.
Hope you all like it! And if anyone has suggestions on how to improve the character, or sees mistakes I made, let me know!
edit: changed wizard 3 to 5, and Arcane Trickster to 7, as it was pointed out that I made a really stupid mistake. Fixed Sneak Attack and final damage outputs.