not sure its been mentioned before (and its more of a typ-o).. in the class documentation:
Dark Blessing - Dark Blessing requires evil alignment to grant its Charisma bonus to saves. - At Blackguard 20 and total character level 35, Blackguards can acquire an item which will let them summon an enhanced fiend with the Epic Fiend feat.
Listen - Increases your chances of hitting concealed enemies. Up to a skill of 60, the enemy concealment drops to (Concealment ** (1 + (Listen skill / 60))). With a skill above 60, the enemy concealment drops to (Concealment ** (1.5 + (Listen skill / 120))). - A Listen skill of 60 is equivalent to having the Blind-Fight feat in reducing enemy concealment, and skill and feat do not stack. '**' is the exponentiation operator. - If the above sounds too complex, remember that effective enemy conceal will be shown in-game.
The Math is both broken and incomplete it's unsolvable. Also if it is correct can you please give and explanation and break it down? Or at least simplify the formula. So it isn't complex.