When Arya Stark saved three men from being burned to death in a mobile cage, she didn't know what it was she was letting loose into the world again. Jaqen H'ghar was the name he gave, and the face he wore, but a man is more than just these things. H'ghar was one of the Faceless Men, the visage-shifting servants of the god of death who are some of the most legendary assassins in the whole of the Game of Thrones universe. Their fees have been known to empty treasuries, yet Arya could give this man three names, and the man would do the rest.
Nearly supernatural in his skills and abilities, there is a great deal of speculation about what the Faceless Men truly are. If you want to mimic their mantle in your next Pathfinder campaign, though, this guide will help get you started on the road to leaving your true nature behind.
More Game of Thrones character builds just like this one are listed on the Character Conversions page of the gaming blog Improved Initiative.
For the historical group that provided some of the inspiration for the Faceless Men, Secret Societies: The Facts About The Order of Assassins may be an eye-opener.
Attributes, Race, and Traits
Despite their bizarre powers, the Faceless Men all seem to be human. Or that's how they begin, at least. For this particular build it's important to build your Intelligence modifier as high as you can, though Charisma and Wisdom shouldn't be left behind. Whether you rely on Strength or Dexterity will depend entirely on which of the two attributes you plan on fighting with. Constitution shouldn't be ignored, but Faceless Men are not warriors who fight while facing their enemies. They are killers, who fight from the shadows, and who bring death to their targets by subtle, often undetected, means.
When it comes to Jaqen's traits, we know very little about the person he was before he became a Faceless Man. However, traits that would make sense for someone who came to the black and white doors in Braavos might include Cosmopolitan (+1 trait bonus on Linguistics checks, and Linguistics is always a class skill for you), Convincing Liar (+1 trait bonus on Bluff or Intimidate, and the skill you choose is always a class skill), Without a Past (gain +1 on Bluff and Linguistics checks to forge documents, and one of those skills becomes a class skill), or Inured to Death (+2 bonus on all checks to resist death effects).
We may not know who the Faceless Man who once went by Jaqen H'ghar was, but we can get an idea of the sort of life he led once he became an acolyte of the red god.
Jaqen is a man of many talents and skills, but the most notable is his ability to blend into the background by taking on a new face, and a completely new persona to match it. He can, in fact, take on a new face with the same ease that normal people might adopt a new name. That is a unique skill... but not an impossible one to put on your character sheet. All you need are six levels of the Urban Druid archetype, which grants you the power Thousand Faces. This lets you alter yourself at-will, becoming any Small or Medium humanoid creature. The class also grants you bonuses against divination and enchantments (since a magical disguise won't work if diviners can simply zero in on your position), as well as access to a domain. Of the available choices, Knowledge is best for those who want to focus on becoming a part of the scenery, and Repose is more useful for those who will deal with the dead and the dying.
In addition to the class features, simple druid spells like Pass Without Trace or Invisibility to Animals can make it possible for an assassin to slip right into a camp, past watch dogs, kill a target, and then walk right out again with no one the wiser until morning. This is in addition to other useful spells that let you endure elements, heal yourself, and even collect information from animals in an area to help you form a plan of attack.
In order to expand your repertoire of both skills and abilities, it's a good idea to take at least 1 level of rogue. If you plan on sneaking past traps, then a straight rogue will do the job, but if you plan to operate in populated areas without tripwires and explosive runes, it might be a good idea to take a level of the Poisoner archetype. We've seen how the Faceless Men, and their apprentices, make use of chemical concoctions to bring death, even if it isn't the preferred tool for the character in question.
Lastly, in order to truly embody a role, you top the classes off with the Master Spy prestige class. The Master Spy allows you to evade lie-detecting magic, resist or nullify divination to find you, or to find out about you. It allows you to hide magical auras, and lets you assume new disguises quickly. It also gives you additional sneak attack, and the all important Death Attack ability that allows you to instantly assassinate a target after three rounds of study. Even more necessary, though, it allows you to touch someone, and to become that person entirely as far as magical detection is concerned. A truly dangerous power for a crafty assassin, and one that could support the theory that Jaqen H'ghar may well have been Syrio Forel (of course, we won't know until the series is over... if then).
Feats and Skills
Again, a Faceless Man is not someone who stands toe-to-toe with his enemies, but rather someone who attempts to be unnoticed. The oyster seller with the friendly smile, the old man begging for alms, or even the prostitute wrapped in silk... they take on the roles of unseen servants and forgotten faces in the crowd. That is not to say that they are only useful in these situations, only that those times are when they are most powerful.
When it comes to skills, there are many you will need. Bluff, Disguise, Perception, and Sense Motive are all required for entry into the Master Spy prestige class. In addition to these skills, Stealth, Acrobatics, Escape Artist, Diplomacy, Linguistics, Sleight of Hand, and even Use Magic Device will all be quite useful. Knowledge skills in particular can help you build a persona, and tell you the lay of the land when you are on a mission.
As to your feats, you will need Deceitful and Iron Will to take levels of Master Spy. Beyond that, though, it will depend on how you choose to fight, and what role you wish to fill within your party.
For example, if you want to deal a great deal of non-lethal damage to your opponents, allowing you to knock people out in combat rather than simply killing them out of hand, then the Sap Adept and Sap Master feats (Ultimate Combat 116) may appeal to you. If you combine them with the Enforcer feat (Advanced Player's Guide 159) you have a build that sneak attacks for big amounts of non-lethal damage, and leaves opponents shaken for minutes on end.
Alternatively, if you wish to focus yourself on stealth, attacking only when you have the advantage of being unseen, then feats like Skill Focus (Stealth), Stealthy (Core Rulebook 134 and 135), and Hellcat Stealth (Cheliax: Empire of Devils) will give you big bonuses to your Stealth checks, and allow you to make Stealth checks in normal or bright light even when you're being observed, albeit at a -10 penalty.
Unlike straight martial or casting classes, this blend gains its biggest opportunities from clever combinations of strategy, feats, spells, and skill checks which put opponents on the defensive. Something as simple as a false surrender to get you brought into a camp, followed by an escape, taking the guard's form, and then killing your target while there's commotion all throughout the camp as people look for the "escaped" prisoner, is the sort of scenario this character might invent. Or maybe you decide to create a clever diversion, like casting obscuring mist, changing into one of the enemy's forms, then running out of the cloud to regroup with your "allies". Then you strike a decisive blow against the leader, and fade away into the mist again, leaving chaos in your wake. Pretty soon, no one can trust that anyone else is really who they say they are, and that confusion grants you, and your allies, a distinct advantage.
There are many ways you could bring a Faceless Man to Golarion. For example, he may be a member of the Red Mantis Assassins, who follow the red Mantis god of death. He could be an elite field agent, tasked with long-term insertions by the Lion Blades of Taldor. He could be a holy warrior, or simply the product of a lifetime of training by a shadow organization. Perhaps he's on the run from his previous life, but has found that by giving up who he was, it's nearly impossible to become someone new for any real length of time. He may even be an agent of one of the constantly feuding nations, like Cheliax or Andoran; the sort of tool they would never claim to use, but which they'll employ in secret without a second thought.