In my next session, there's a good chance that the players will interact with a Kobold Ranger that has been following them around. It might even come to combat. However my players, being aware that Kobolds hate Gnomes, have decided that they will disguise the party's Gnome as a Halfling.
This led me to an interesting question, as this Ranger has Gnomes as one of his Favored Enemies but is likely to be fooled by the very convincing disguise. Will he still get his +2 bonus to skill checks and damage rolls against this Gnome if he doesn't know he's fighting his favored enemy?
The text only mentions that the target has to be of the specified type which the Gnome certainly is, but I'm not sure whether it's intended that he would still hit for extra damage if he thinks he's fighting (or tracking, or bluffing) a Halfling.