I don't know if this question has been addressed before, but I couldn't find anything on it. The Infiltrator archetype replaces Favored Terrain for a different ability; however, it never says anything about Camouflage or Hide in Plain sight being changed.
Both of these abilities only function within the Ranger's Favored Terrain so what happens to them? Does the Ranger just receive these now useless abilities?
Another question: if the Ranger gained a favored terrain from a different source (such as the Horizon Walker, or the Rogue Talent) would these useless abilities then begin functioning or is it just assumed that since they serve no purpose to an infiltrator they are never gained?
There's an FAQ on that here:
Ranger: How does a ranger with the infiltrator archetype (page 126), which causes him to lose his favored terrain class feature, use his camouflage and hide in plain sight class features?
A ranger with the Infiltrator archetype can use the camouflage and hide in plain sight class features whenever he is using his adaptation class feature, regardless of the terrain he is in.
Update: On page 126, in the Infiltrator archetype, in the adaptation class feature, add the following sentence to the end of the second paragraph.
The ranger can use the camouflage and hide in plain sight class features whenever he is using adaptations.