We are playing (a converted) City of the Spider Queen and a player whose character died has now created a new one; a Dwarven Rogue. He asked me if he can take the Ancient Enmity Alternate Racial Trait from the Advanced Race Guide:
Ancient Enmity: Dwarves have long been in conflict with elves, especially the hated drow. Dwarves with this racial trait receive a +1 bonus on attack rolls against humanoid creatures of the elf subtype. This racial trait replaces the hatred racial trait.
The only reason he asks this is because he knows he will be facing a lot of drow. If he were starting at level 1, I would allow this. But his new character is level 8, and has no reason whatsoever to have hatred vs elves, since drow only recently roamed the area. Also I don't think it's fair to the other players, who still have their original characters.
Does anybody has some advice, or faced the same problem?