I was looking at the rogue talents and found something a little confusing. According to the Terrain Mastery talent:
Benefit: A rogue with this talent gains a favored terrain as the ranger ability of the same name, though the favored terrain ability does not increase with her level as the ranger’s ability does.
Special: A rogue can take this ability multiple times, each time applying it to a new terrain, and granting all other favored terrains a +2 increase to the favored terrain bonus.
According to the special rulings of the talent, that would mean if you selected Terrain Mastery 10 times (10 talents for a lvl 20 rogue), you would receive a +20 initiative, Knowledge Geography, Perception, Stealth, and Survival.
Continuing off this logic (for a lvl 20 rogue), that would mean you can get feats that increase your damage, accuracy, perception, and stealth and thus make you the "ultimate" rogue.
(and for those who say if you spot the rogue before they stealth, they could have the feat Hellcat Stealth)
Please comment to compliment or argue my logic.
Rogue -> Horizon Walker, take Terrain Dominance (Urban). Congratulations, at about 9th level you could have a +16 to attack and damage against anything that might live in a city (such as all humanoid types).
(For reference: Terrain Dominance allows you to use your favored terrain bonus as a favored enemy bonus against anything native to the terrain.)
EDIT: I suppose I should note that yes the above is obviously stupidly overpowered. Most favored terrains aren't a problem for that ability, but Urban covers so much because basically anything civilized would count as native to Urban. Heck, most people think Favored Enemy (human) is overpowered, much less something that covers that and so much more.
The magnitude of the bonus is mostly a problem with the rogue talent, not the terrain dominance ability. The most extreme Ranger + Horizon Walker combo would top out at about +14 and require sacrificing the idea of having much of a bonus in other terrains, but the Rogue way allows you to hit a higher bonus at less than half the level and without sacrificing the bonus you get for other terrains.
Horizon Walker does eventually treat all terrain, as a Favored Terrain.
Yup. Combine this with 10 levels of rogue and you could end up with a +8 bonus in all terrains (much higher in most) and hide in plain sight.. everywhere. Good luck finding that guy without magic!
Do note, however, that Horizon Walker only gets to use their favored terrain bonus as a favored enemy bonus in 3 terrains. Forest and Urban would cover most things, though. Maybe select Underground or one of the evil outsider planes as the third.