The party consists of five level 15 PCs:
1 Cleric 5 / Exorcist of the Silver Flame 10 - shtick is spell support, and spells that do many nasty things to evil outsiders, hp high 90's, AC 22
1 Half-Dragon Monk 12 - shtick is massive unarmed damage and moderately powerful sonic breath weapon AC 31, hp low 100's
1 Half-elf Monk 15 - shtick is nigh-unkillable, and pretty decent damage in melee. AC 30 to 35 (expertise), hp mid 100's.
1 Changeling Artificer 10 - shtick is ungodly amounts of magical items, AC 35, hp high 90's.
1 Ratling Ninja 13 / Shadowdancer 2 - shtick is unaparalleled stealth and sneak attacking flat-footed foes. AC 33, hp low 100's.
When prepared (as they will be for this battle), the monks are usually equipped via Artificer infusions with both Vorpal and Wounding enchantments on their hands. (thanks to a feat, their attacks can do slashing) The artificer can cast a number of spells from Staff or scroll of 7th to 9th level power, and uses spells from the Spell Compendium frequently, including frequently going around with superior invisibility in major conflicts.