The barbarian hero has been an icon of fantasy ever since Conan trod the kingdoms of the earth beneath his sandaled feet, and an archetype of roleplaying games ever since the first PC kits were released in the 2nd edition of Dungeons and Dragons. For those playing Pathfinder, the barbarian base class is always a great option. Especially when you consider all the archetypes the class has, allowing players to customize their concepts.
If you're looking for some truly unique takes on barbarian characters, that pack a powerful punch, then you might want to consider these 5 multiclass cocktails.
Also, if you're looking for general advice on playing better barbarian characters, then 5 Tips For Playing Better Barbarians has you covered. Lastly, if you want a unique take on the Rage mechanic used in Pathfinder, then 50 Shades of Rage: Flavoring The Barbarian's Signature Power might be right up your alley.
#1 The Rogue
For some reason, there are players who think barbarians and rogues are completely incompatible. After all, how does a big, hulking brute with an ax dovetail with a sneaky, stealthy guerilla?
Pretty well, since you ask.
You see, the barbarian and the rogue were meant to go together. Sort of like chocolate and peanut butter. In fact, since a barbarian gets Uncanny Dodge at second level, and a rogue gets it at 4th level, combining those two into a 6th level character will give you Improved Uncanny Dodge. That's one level later than a straight barbarian, but two levels earlier than a straight rogue. The same is true of their Trap Sense, which stacks.
What sort of circumstances would create a barbarian/rogue combo? All kinds! For example, a half-orc ambush expert could combine the Rogue Talent Fast Stealth with sneak attack, darkvision, and Rage to leap out of the shadows, wreak havoc, then vanish into the darkness. The combination could work for someone who was part of an irregular army unit as well, trained to use unusual tactics and powers to achieve victory. It might even be someone who grew up as a sneak thief, but who realized that when you're strong enough you can take what you want regardless of who's looking.
#2 The Alchemist
The alchemist seems like it would be the polar opposite of the barbarian. After all, one is a studious scientist uncovering the secrets of bizarre elixirs, and the other is a brutal warrior who relies on passion and wrath to destroy his enemies. They should go together like oil and water... but the combination is much deadlier.
As an alchemist, a barbarian suddenly has access to self-buffs. Bull's Strength, for example, is a basic trick he could keep on-hand for the next fight. However, there's also Mutagen, which produces an alchemical bonus to a physical stat. So, if you want to really hulk out (as seen in How to Build The Incredible Hulk in The Pathfinder RPG), you can combine the morale bonus from Rage, the alchemical bonus from your mutagen, and an enhancement bonus from Bull's Strength, and wind up with a +12 bonus to your strength score at a fairly low level. A +14 if you use the Ragechemist alchemist archetype. If you add in Discoveries like Feral Mutagen, which gives you natural attacks and an Intimidate bonus, then you're going to see some serious effects.
The difficulty with these two classes is getting enough high stats to go around. Barbarians need Strength and Constitution (if you're a standard, melee brawler), and alchemists need Intelligence (for their bombs, extracts, and other things). This combination takes a chunk out of your Will save, too. So it's important to look at your goals, and to build accordingly. A dip in barbarian gives you better weapon and armor proficiencies, Rage, and Uncanny Dodge. A dip in alchemist gives you mutagens, extracts, bombs, and some bonus feats. There's no wrong way to combine these ingredients together, but different combinations will achieve wildly different results.
#3 The Samurai
A variant of the cavalier, the samurai is a wholly separate beast. This class is less reliant on its mount, and it gains access to the unique Resolve ability. Resolve allows a samurai to push through certain conditions, ignoring their effects. Fatigue is one of those conditions, and it is the bane of any barbarian character who needs the benefits of Rage, but has to wait for their second wind.
That's where The Barbarian Samurai comes into the picture. This character combination can do a Rage cycle (when you Rage, drop out, then use another ability to eliminate the fatigue so you can Rage again) fairly early on. The question you need to ask is are you a barbarian with a few levels of samurai, or a samurai with a few levels of barbarian? Because if you only have 2 or 4 levels of barbarian, then Rage Powers like Smasher are going to be your best bet since they aren't reliant on how many levels of barbarian you have. If you only want a few levels of samurai, though, then your Order abilities are never going to mature, and you may want to be careful of your Mount, since he won't progress with you. Leadership, though, could gain you a special mount as a cohort, if you feel you must have a loyal companion.
#4 The Swashbuckler
The traditional image of the swashbuckler, the acrobatic swordsman with a light, highly mobile weapon, is not what most people think of when they think of the barbarian. Barbarians, or so the common wisdom goes, wield greatswords and battle axes, and are more reliant on sheer, brute strength than they are on finesse and speed.
Of course, the common wisdom is rarely universal. Because it's entirely possible to build a brutal swashbuckler. A morning star, after all, is a one-handed piercing weapon, and thus gains all the benefits that come with a swashbuckler's class features. The same is true of a spiked gauntlet. However, it's also possible to take feats like Slashing Grace, which will allow you to add your Dexterity to your damage, and turn any one-handed slashing weapon (like a bastard sword or a dwarven war ax) into a piercing weapon for the purposes of your swashbuckler class features. You can also take the barbarian archetype Savage Technologist, which gives you a bonus to your Dexterity and Strength when you Rage, and gives you no negative to your AC.
So, whether you're a whirling dervish, a dagger-wielding bravo, or an enforcer who can do terrible things with that short sword on your hip, this combination is a nasty little number.
#5 The Gunslinger
Gunslingers are one of the most divisive classes in the Pathfinder RPG, but even people who like mixing black powder with high fantasy don't always see the advantage in giving guns to the barbarian. After all, they don't really work at range as well as they do up-close and in-your-face.
Unless you build them that way.
The Savage Technologist archetype gives a barbarian the ability to use guns, but there's a big difference between being able to use guns, and being a gunslinger. For example, the Savage Technologist can deal their Dexterity modifier as a bonus on damage with a firearm at 5th level, just like a gunslinger can, but they don't gain grit or deeds. Nor do they gain Nimble, which is ideal for a lightly armored, but heavily armed, combatant. The gunslinger adds an initiative bonus, a variety of options, and a lot of nasty tricks. And if you pair gunslinger with a standard barbarian, then the combination can be even deadlier. Just remember you're taking a hit to your saves (though not your BAB), and you need to choose your Rage Powers and feats with care. Ask yourself what you're going to do when you run out of bullets, or when someone closes with you. That's when an ax-musket seems like an ideal option.
Who are these black-powder barbarians? Well, they might be wanderers in a wasteland where magic is even less reliable than their roaring guns, staying alive only because of their quick wits, and fast hands. Perhaps they're elite mercenaries whose weapons and fighting methods are unique to them, and not taught to outsiders. They might even be wandering warriors who adopted a new form of weapon, then brought it back home with them.