438a3a28_es___Dungeons_and_Dragons_Wiki__Perk_Benefit
[Perk Name] Advanced Formation [Pro Perk Benefit] Adjacent Allies gain a leadership bonus to AC equal to your Charisma Modifier. [Perk Benefit] 
Adjacent Allies gain a leadership bonus to AC equal to 1/2 your Charisma Modifier.
CoDnD- Call of Duty 3.5 (3.5e Sourcebook)/Chapter 2: New Rules - Dungeons and Dragons Wiki
Perk Benefit