I'm still not too keen on Favored Terrain for a ranger. I took a while to think about it and here's why:
1) Favored terrains do not work indoors. Every other class is still at full strength while indoors (including the druid, who can memorize other spells than call lightning and entangle.). A ranger with favored terrains is not. This is especially noticable whenever the campaign drifts to a dungeon.
2) A ranger who logically specializes in a certain terrain is penalized when the party travels to a new terrain type. (Which is a common occurance.) Which leads to...
3) A PC ranger with specialized favored terrains is going to constantly force the rest of the party to stay within those boundaries, to the detriment of the campaign.
4) A ranger who doesn't specialize (and takes one of each terrain type) is nothing more than a fighter with one terrain (because only one is active at a time), five feats and track.
5) Favored terrains only work on the material plane (with areas that you would find on Earth.) It wouldn't really work on the Abyss or the elemental plane of Fire, for example. (If the DM allows an entire plane to work as a Favored Terrain, then there is the problem of too many planes to choose from, i.e. a ranger who takes Acheron wouldn't apply that bonus on the Abyss. Also, why couldn't the ranger take Favored Terrain: Material Plane?)
6) Favored terrains do not make sense. Just because a ranger knows how to survive in one forest, does not mean that he should be as equally adept at surviving in a forest on a different continent (or plane) that has different flora and fauna.
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Honestly, I don't really like
any Favored things, be it Enemies, Lands, Terrains, Beasts or what have you. It kind of goes against the whole idea of a ranger, IMHO. A ranger is supposed to be versatile. Versatility does not mean that the player can choose any sort of Favored Thing. It has to do with the ranger's versatility, not the player's. After a ranger chooses a Thing, he is no longer versatile. Having lots of Favored things to choose from means that the
player has lots of options, but the
ranger does not.
Regardless of which Favored Thing a ranger chooses, he is still specialized, and that specialization is what ruins the versatility of the PHB ranger. Favored Thing falls into the same trap, regardless of what type of Favored Thing you are talking about.
Example: Fred wants to play a ranger named Cheesehead. Fred has lots of different Favored Terrains to choose from. He asks the DM where the party is located. The DM tells Fred, "A Forest." Fred chooses forest as Cheesehead's first favored terrain.
But the forest in question is next to a river, a mountain range (with some natural caverns), a couple towns, some plains and a swamp (the delta near the ocean)
Cheesehead is specialized in dealing with forests. He will suck rocks when in the caves, mountains, towns, plains, swamp, ocean, dungeons, towers, castles and whatever else is not a forest. (All the way until L4 when he will probably choose one of the above terrains.)
If the story leads the party out of the forest (because the rest of the PCs are not going to stay in a forest forever), the DM can railroad the story back into the forest to appease the ranger, or the ranger can attempt to alter the story by staying in the forest.
If either of the above fails, then the ranger is outside of the forest, and for a while afterwards, the ranger will not be playing at full strength. (until back inside the forest.)
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Anyway, YMMV and IMHO and my 2 cents and all of that.
