Will all of your targets be from the same general collection of enemies? A Cleric20// Urban Ranger X could work well for that:
At the game master's discretion, an urban ranger may select an organization instead of a creature type as his favored enemy. For example, a character might select a particular thieves' guild, merchant house, or even the city guard. The favored enemy bonuses would apply to all members of the chosen organization, regardless of their creature type or subtype.