You should take the beast totem rage powers and make a good two BEAR handed barbarian.
Yes, these are complicated rules. I could half explain them to you, but there are much better people for that on the boards. Bump so one of them can find this thread. Here are some points of importance though.
1) Primary attacks are infinitely better than secondary attacks, because all secondary attacks take a -5 to hit and only add 1/2 str to damage.
2) You need a full round to do a full attack in order to get all of your natural attacks off. You cannot move and get multiple attacks unless you have something like the pounce ability (possible through barbarian rage powers). That means if you move, you get a single attack.
3) You can have basically infinite extra natural attacks as long as they don't use the same body part. You could claw/claw/bite/gore/wing/wing/tail slap if you had a way to get all of those attacks (see dragons for this entire lineup except for gore).
To continue Carl's statement, you want your first rage power to be Beast Totem, Lesser. There's your claws right off the bat. You don't even need to modify your tengu beak attack, which counts as a bite.
And at that point you have three attacks, all at full STR.
Another option would be other races that can chomp. Three that come to immediate mind are orcs, half-orcs (both need a feat) and kitsune (but -2 STR isn't a good start for a barbarian build).
Anyway, when you qualify, you'll end up grabbing both Beast Totem (natural armour bonus that scales, hooray!), and then Beast Totem, Greater. There's Pounce built in, and on top of that your claw attacks are now the equivalent of battleaxes. Enjoy two full BAB swings of d8 plus full STR. (And your bite.)
In fact, a bite attack from your race can help in those times when you're not pissed off at the world or everything in it (there's no build I can imagine that would give 8,640 rounds of rage a day). And those times will be at 1.5x STR bonus too, if that matters (it does).
Don't forget Power Attack, of course. Each natural (primary) attack gets -1 to hit but +2 to hurt. This is worth it.
Finally, you may want to ask this in the Advice forum; I've kind'a flagged this, since it's more of a question on build-a-barb.
To continue Carl's statement, you want your first rage power to be Beast Totem, Lesser. There's your claws right off the bat. You don't even need to modify your tengu beak attack, which counts as a bite.
And at that point you have three attacks, all at full STR.
Another option would be other races that can chomp. Three that come to immediate mind are orcs, [B]half-orcs{/b} (both need a feat) and kitsune (but -2 STR isn't a good start for a barbarian build).
In fact, a bite attack from your race can help in those times when you're not pissed off at the world or everything in it (there's no build I can imagine that would give 8,640 rounds of rage a day). And those times will be at 1.5x STR bonus too, if that matters (it does).
Half-Orcs have a alternate racial trait, if your DM allows you to take it, called Toothy, giving you a bite attack instead of Orc ferocity. Same as the Razortusk feat, but toothy is always a primary attack. The Razortusk feat makes the bite a secondary if it is part of a full attack. The rage power Animal Fury gives you a bite attack, but has the same issue as Razortusk, counts a secondary when used in a full attack.
If you wanted to stick with the monk route your only option is Martial Artist, as to rage you need to be unlawful and all but that monk archetype needs to be lawful.
Half-Orcs have a alternate racial trait, if your DM allows you to take it, called Toothy, giving you a bite attack instead of Orc ferocity. Same as the Razortusk feat, but toothy is always a primary attack. The Razortusk feat makes the bite a secondary if it is part of a full attack. The rage power Animal Fury gives you a bite attack, but has the same issue as Razortusk, counts a secondary when used in a full attack.
If you wanted to stick with the monk route your only option is Martial Artist, as to rage you need to be unlawful and all but that monk archetype needs to be lawful.
I think those are pretty poorly written in the original books; usually what makes a primary natural weapon secondary is when you start using manufactured weapons (thus, chomp plus greataxe means greataxe at full BAB, bite at -5). I'd expect either variations or arguments about whether Razortusk would really dive like that when used with claws from elsewhere. (Animal Fury in Unchained was clarified better.)
It might not fit what you're going for with your character, but getting a Throwing 2-handed weapon like an Earthbreaker would be a very fun idea. You could toss it at one enemy before going after another with your claws. Personally, I would go Half-Orc for the favored class bonus and access to a bite attack, but you could do the same thing with Tengu minus the really good favored class bonus.
Half-Orcs have a alternate racial trait, if your DM allows you to take it, called Toothy, giving you a bite attack instead of Orc ferocity. Same as the Razortusk feat, but toothy is always a primary attack. The Razortusk feat makes the bite a secondary if it is part of a full attack. The rage power Animal Fury gives you a bite attack, but has the same issue as Razortusk, counts a secondary when used in a full attack.
Just as a note it does not really say that it is always a primary attack under Toothy, it just says that it is a primary attack. So, if you use it as part of a full attack, I would probably rule that it is at -5 to hit and half strength, but I can see how the wording would make most think otherwise.
I just run Toothy, Razortusk, and Tusked as the same benefit.
While it takes time to take off fully, you could also try for unarmed strikes.... and actually skip beast totem.
I know- HERESY!
But hear me out- pummeling style is made to cover a lot of the problems unarmed strikes usually face. And while it is much, much easier for the unarmed classes (monk, brawler), it can be grabbed later using just plain BAB instead. So anyone can use it.
Pummeling style gives you clustershot with your unarmed strikes. So that takes care of DR problems (also, barbarians have access to furious enhancements, which also means they can get good enhancement bonus on an amulet of might fists for cheap; that can also get through DR).
Next, there is pummeling charge, which is pseudo pounce and can actually make beast totem obsolete. It comes a bit late (BAB+12 prereq), but it does the job. You may wish to consider a dip into master of many styles monk to get ahold of this more easily.
And if you forgo beast totem... you could do other things. Such as dragon totem- yes, get ALL THE DR! DROWN IN IT!
Half-Orcs have a alternate racial trait, if your DM allows you to take it, called Toothy, giving you a bite attack instead of Orc ferocity. Same as the Razortusk feat, but toothy is always a primary attack. The Razortusk feat makes the bite a secondary if it is part of a full attack. The rage power Animal Fury gives you a bite attack, but has the same issue as Razortusk, counts a secondary when used in a full attack.Just as a note it does not really say that it is always a primary attack under Toothy, it just says that it is a primary attack. So, if you use it as part of a full attack, I would probably rule that it is at -5 to hit and half strength, but I can see how the wording would make most think otherwise.
I just run Toothy, Razortusk, and Tusked as the same benefit.
I can agree with this. As i am just reading off of the d20SRD and not the book Toothy came from. Who is to say that this is not a shortened version and just missing it.
Either way Toothy would free up a feat slot/rage power slot
If you're willing to mix "bare" hands and actual weapons, you could also go the Bloodrager/Dragon disciple road for an insane strength bonus and some nice perks. And a hell of a style.
The Dragon bloodline gives you 2 claws right off the bat, a good elemental resistance, some natural armor plus a breath weapon later on.
The claws don't last long per day (but are reinforced by your element), therefore you must be willing to mix, say, an earthbreaker and your claws.
The Dragon disciple prestige class will give you a good bite pretty quickly (primary and soon enhanced by your element), and then improve your natural armor, your strength and constitution.
And later on, freaking wings and Dragon form!
As a bloodrager you also get the ability to cast some great self buff spells like enlarge person, mirror image...
Obviously it doesn't give you access to Beast totem, but I reckon some ways to get the next closest thing, aka pummeling style were mentionned earlier.
Now picture a large sized enraged half-dragon charging from the sky and beating the s**t out of everything in its path with his claws and teeth harnessing the force of a trainwreck, and then tell me you don't want to try it.