I'm about to start a Barbarian Shaman, need some ideas

[Coyote81]

So having talked to my DM already, I plan on making a Barbarian Shaman, and I need some ideas for optimizing.

There are only to things that have to stick. Barbarian to 6 then runescribe to 5, I need ideas to fit this build idea.

-Should I go dex Barbarian, or just get my dex/int to 13 and then str/con the rest?
-race?
-Feats(if human varient), I think i will need all my ASIs
-What to plan on doing after rune scribe?

I look forward to some great ideas. I'm starting at level 3 for this campaign.

[Tesla_pasta]

Alright, so I think the best way to approach this is to use runes as melee buffs before raging, then raging in combat. This means your spell saving throws will be less important than combat stats, so maxing dex first is a priority. Barb 5 gives you two attacks, so you can get a lot of mileage out of the Brand abilities. I think two weapon fighting is a good option here. Constitution should also be as high as possible for more durability, since you lose out on barb hit dice after 5 level.

so using arrays

15 dex, 14 con, 13 int. Pick a race that lets you max dex quickly, then con. with 20 dex and 16 con, your AC and HP are pretty solid and you've got good bonuses to hit. Runescriber dosen't make a ton of use of bonus actions, so wield 2 short swords and make offhand attacks as often as possible to maximize rage bonus damage. Each morning, you can attune each of your weapons with whichever brands will be most effective.

Good luck!

EDIT: if you're going Path of the Berserker, there is no need to wield 2 weapons, and it might be worth going STR and Armor instead, and seeing if you can do silly things with Howling Brand on a reach weapon.

[Arkhios]

So having talked to my DM already, I plan on making a Barbarian Shaman, and I need some ideas for optimizing.

There are only to things that have to stick. Barbarian to 6 then runescribe to 5, I need ideas to fit this build idea.

-Should I go dex Barbarian, or just get my dex/int to 13 and then str/con the rest?
-race?
-Feats(if human varient), I think i will need all my ASIs
-What to plan on doing after rune scribe?

I look forward to some great ideas. I'm starting at level 3 for this campaign.

If you're using point-buy method to generate ability scores, you might want to consider not trying to boost both your dex and con to the top. Instead, you can still benefit from rage while wearing medium armor. Thus, you can either leave your dex to 13, or increase it by +1 (either with a feat or along with int, of that's 13 as well). With the best medium armor (half plate: AC 15 + max dex: +2) you would still reach AC 16 or 17, which is quite enough. That's same as with chain mail or splint mail (heavy armors).

Dex barbarian doesn't work with rage, as your bonus damage applies only when you make a melee attack using strength.

After Rune Scribe, just get back to being barbarian.

Totem Warrior Primal Path is an excellent choice to emphazise your shamanism, and you even get couple of druid spells as rituals only.

With Point-buy variant human (+1 str, +1 con, Durable (+1 Con):
Str 16, Dex 13, Con 14, Int 13, Wis 10, cha 8
(9, 5, 4, 5, 4, 0) You would guarantee your access to Rune Scribe, at the cost of lower hit points, but that's alright. You still have rage, and can benefit from strength, and you can use armor instead of bare skin.

[Coyote81]

If you're using point-buy method to generate ability scores, you might want to consider not trying to boost both your dex and con to the top. Instead, you can still benefit from rage while wearing medium armor. Thus, you can either leave your dex to 13, or increase it by +1 (either with a feat or along with int, of that's 13 as well). With the best medium armor (half plate: AC 15 + max dex: +2) you would still reach AC 16 or 17, which is quite enough. That's same as with chain mail or splint mail (heavy armors).

Dex barbarian doesn't with rage, as your bonus damage applies only when you make a melee attack using strength.

After Rune Scribe, just get back to being barbarian.

Totem Warrior Primal Path is an excellent choice to emphazise your shamanism, and you even get couple of druid spells as rituals only.

With Point-buy variant human (+1 str, +1 con, Durable (+1 Con):
Str 16, Dex 13, Con 14, Int 13, Wis 10, cha 8
(9, 5, 4, 5, 4, 0) You would guarantee your access to Rune Scribe, at the cost of lower hit points, but that's alright. You still have rage, and can benefit from strength, and you can use armor instead of bare skin.

I think you convinced me to go away from a Dex build, I was having a hard time with the low to hit and not being able to use rage damage if I use dex, thanks

[Arkhios]

Because of Rune Scribe you won't get a conventional ASI at its 4th level, since you can change it every day to grant different modifiers. So in the end, you'll have only 3 default ASI, which I'd recommend putting in Strength, Con, and/or Feats. Since with Living Rune you can modify your stats at your whim, consider leaving strength at 18, increase both dex and int to 14 (if using the array I suggested), and maybe increase your Con to 16, or take feat if you think you need one.

You could, though, consider taking levels in fighter. I agree that the brands would mesh well with two-weapon fighting, but to be better at it, I would want the Two Weapon fighting style, to be able to add my strength modifier to damage with both weapons.
If you choose to go with fighter beyond barbarian 6/Rune Scribe 5, maybe take the Eldritch Knight subclass for the rest 9 levels you have. You would get one additional ASI in the process, effective 3 more levels for spell slots progression - landing at 8th level (slots: 4/3/3/2, iirc), synergy with higher than average int, and Fighting Style, Action Surge, and the very neat Battle Magic. For Cantrips I'd definitely suggest Booming Blade and Green-Flame Blade; even though you couldn't cast them while raging. Obviously your playstyle would be drastically different from the common barbarian, but is that a flaw? I don't think so. Thinking outside the box can be very rewarding :)

EDIT1: As I understand, the runes and their abilities function as if they were magic items (=not spells!), so using them might actually be possible while in rage. Using the runes speaks only about "expending spell slots", and nothing about "casting a spell", so I'm quite positive that they can be activated even when raging.
EDIT2: You could ask if your DM would allow replacing eldritch knights base spell list for druid instead of wizard, and maybe change abjuration for transmutation. In my opinion, it wouldn't be a game breaking alteration.