I have just recently reached lvl 11 with my character and I was planning to continue with horizon walker. Levels in classes so far are ranger (guide/trapper) 6/rogue (trapsmith) 4, and my first favored terrain is underground. Which favored terrains would be best for the general purpose when the concept is an ultimate archaeologist and pathfinder to the core?
Any terrain would fit the theme. Archaeological finds can pop up anywhere. Terrain isn't such a massive hurdle for advanced civs, less so for those aided by magic. Deserts, plains, tundra, forests, jungles, even marine environments in the RL contain archaeological sites.
I'd pick the ones you're likely to encounter most.
Thanks for advices.
Urban indeed seems to be along the line with underground for an archaeologist, so that's what I'll be taking now. After that, I suppose any terrain will do, perhaps judging by which ones I encounter (or have encountered) the most, as Verteidiger said.
Which terrain you will encounter most often is relevant as far as which favored terrains to stack the Favored Terrain skill/initiative bonuses in (Urban should be maxed, after that is a judgement call). But the more important thing is the unique abilities of Terrain Mastery/Dominance, which function even when you are not in those terrains. You need to first select them as Favored Terrains before you can take the Terrain Mastery/Dominance, but it doesn't matter for Mastery/Dominance if you ever boost the amount of skill/initiative bonuses in those terrains.
Good ones to grab as far as Terrain Mastery/Dominance abilities:
Underground (which you already have as Favored Terrain):
Mastery: Blindfight Feat (nice if you are melee specialist)
Dominance: Darkvision or increase existing DV by +60' (nice)
Ethereal Plane:
Mastery: Ignore 20% Miss Chance from Fog and Mist, and treat Total Concealment from those sources as Concealment (nice)
Dominance: Ethereal Jaunt SLA 1/day (min level 7) (nice)
Swamp:
Mastery: +4 competence bonus to Perception (nice)
Dominance: Tremorsense 30' (min level 5) (nice)
Aligned Planes (choose one per favored terrain):
Mastery: Detect as that Alignment as Immediate Action (weak)
Dominance: All your attacks (natural/manufactured) count as the opposite Alignment for purposes of DR (great)
Astral Plane:
Mastery: Fly speed increases by 30' on planes with no gravity or subjective gravity (weak)
Dominance: +1 att/dmg vs. Outsiders, Dimension Door SLA 3+WIS times/day (nice)
Desert and Water/Plane of Water have some decent abilities too, though I won't list them individually.
I'm not actually sure about the minimum level reference, e.g. Ethereal Dominance references minimum level 7, but you don't get a Terrain Dominance at level 7 of Horizon Walker, and you don't get another one until level 9. The Ethereal Dominance could not be possible to fit into your character build before Char Level 20, based on RAW.
By level 7 of Horizon Walker (char level 18 for you, about as high as you can get with PFS), you will have 3 Terrain Masteries and 2 Terrain Dominances.
You will have 5 favored terrains from Horizon Walker, plus 1 from Ranger, for a total of 6. Subtracting 3 for your Masteries/Dominances, that leaves you 3 for whatever terrains you want to pick the skill bonuses in, I guess terrains you would commonly expect to be in: Urban is a good one even if you also get Underground, the others are up to you... I would put the highest increases to the amount of skill/initiative bonus into Urban, the rest are your call.
That's what I'm going to do, puff up Urban to +4 at this point.
more specific details of the said character: He's an archer, emphasis on both single devastating shots (vital strike+sneak attack etc.) and "rain of death" (rapid shot+manyshot) depending on the situation at hand.
So I should keep that in mind when picking up those few masteries and dominances I can.
ofcourse, there is also the option to take Rogue's Terrain Mastery via extra rogue talent feats to get a wider spread of terrain options for both the Masteries and Dominances, but also for Guide's Terrain Bond ability (and further ridiculize the "dominance as favored enemy" against certain creatures)