[Joe_G_Kushner]

Off the top of my head for example, there's a PrC that's missing it's hit dice. Ah, here's John Cooper's notes. The man is an editing mecahnic machine.

"p. 42, Sothillis, male elite ogre mage sorcerer 12/legendary leader 5: AC should be 22, not 23 (-1 size, +5 natural, +8 +4 mithral shirt). Ditto with his flat-footed AC.
pp. 59-60, Sunlord Daelegoth Orndair, male elite fire genasi cleric 10/sunmaster 10/evangelist 5: Initiative should be +8, not +3 (+4 Dex, +4 Improved Initiative). AC should be 24, not 20 (+3 maximum Dex while wearing a breastplate, +7 +2 breastplate of command, +4 +2 blinding mithral heavy shield). Touch AC should be 13, not 9. Flat-footed AC should be 21, not 20. I don't think his "Ref +7" is correct, since he gets +3 as a Clr10 and +4 from Dex; that's +7 right there - surely 10 levels of sunmaster (from Lost Empires of Faerûn) and 5 levels of evangelist (from Complete Divine) should grant some extra Reflex bonuses? (Even if both prestige classes provide poor Reflex saves, that would be +3 and +1, respectively, bring the Sunlord's total up to +11.)
pp. 99-100, Erthaer Javilarhhsson, male ghost (augmented elite Illuskan human) ranger 13/dread commando 5: His "Senses" line reads "Spot +23, Listen +23" but under "Skills" they're both listed at +31.
pp. 121-122, Imvaernarho, male red great wyrm, advanced: Will save against his frightful presence should be DC 51, not DC 41 (10 + 1/2 HD + Cha bonus = 10 + 30 + 11).
pp. 124-125, Mhair Gulzabban, male Calishite human wizard 15: Melee touch attacks for the spells shocking grasp and vampiric touch should be +5 melee touch, not +10 (+7 BAB, -2 Str); they're not ranged touch attacks, where the +10 touch attack would be correct.
p. 125, Sharaera Duthtue, female moon elf wizard 12: The save DCs given for her spells are all one point too high; they should be at DC 14 + spell level, but they're all listed as if they're DC 15 + spell level. "Immune" line should include "oil of taggit poison" since all five of the Company of the Cloak have built up an immunity over the past few years. Also, her "Combat Gear" line should include the 2 potions of cure serious wounds listed under "Possessions."
p. 126, Horlo Aumrabbar, male Tashalan cleric 13 of Mask: Should have 3+1 6th-level spells prepared, not 2+1 (2+1 as a Clr13, +1 bonus spell for having Wis 22), and 4+1 5th-level spells, not 3+1 (3+1 as a Clr13, +1 bonus spell for having Wis 22). Turn undead should be "(5/day, +4, 2d6+15)," not "(5/day, +5, 2d6+15)" - he has a +2 Cha bonus, and gains +2 for having 5 or more ranks in Knowledge (religion).
p. 127, Omskilar Rethwood, male Tethyrian human fighter 14: Grapple attacks should be at +19, not +16 (+14 BAB, +5 Str)."