here's a build i made for an evil campaign designed to help empower the party necromancer (wiz/urpriest/mystic theurg) - i threw it together today at work so im sure theres room for improvement
Aasimar (buyoff for the LA) Bard 1/Marshal 2/Warblade 2/Dirgesinger 5/Suel Archanamec 2/Jade Phoenix Mage 8
Feats: combat casting, iron will, skill focus diplomacy (free), force of personality, song of the white raven, requiem, undead leadership (not in that order),
Stats:
(32 point buy)
STR: 14 +4 tome +6 belt = 24
Dex: 10 +6 gloves = 16
Con: 10
Int: 14
Wis: 8 +2 racial = 10
Cha: 18 +2 racial +5 level +5 tome +6 cloak = 36
AC 29 = 10 + 9 (+5 mithral midnight chain) + 7 shield (+5 mithral animated arrow deflection heavy shield) +3 dex
-- uncanny
fort 13 = base 13
reflex 13 = base 8 +3 dex +2 +2 insight (from int)
will 16 = 14 base +2 iron will
+13 more against mind affecting
+2 in white raven stance
+2 more against death/fear effects
BAB 15/10/5
+5 adamantine greatsword (wounding keen spellstoring)
+1 marshal aura
+7 str
+1 inspire courage
full attack:
+29/+24/+19
damage 2d6+15 (+1 inspire courage)
attacks enhanceable by burning archanamech caster slots (which you have tons of b/c of the high cha)
all FLANKING allies gain an additional +13 damage to EACH ATTACK
bardic music 6x a day (bard + warblade + dirgesong)
countersong
fascinate
inspire courage
song of sorrow
song of bolstering
song of grief
song of horror
song of awakening
free empowered/quickened spells whenever yuo succeed martial strike
the key here is to maximize your flanking damage by attracting a necropolitan thrikreen beefed up on multiweapon feats and if possible using dirgesong to help as well
as long as your cohort is flanking at level 17 (with full bab progression) he'll be attacking 16 times around w/ bonuses higher than yours...each of these attacks doing +13 damage - thats 208 damage a turn from the flank bonus alone!
if your dm allows it, you could use gentle repose to store maralith corpses and use dirgesong to activate this, and use it for more flank damage. you can't use spells with this active, but you can expend spell slots to power your firebird stance and arcane wrath.
If you continue to epic levels you get an awesome "im exploding now see you next week" ability as well
the character also makes a formidable diplomacer with good access to social skills, lots of skill points, and high charisma