My Life As A Gamer: The Blade In The Dark

The Assassin is a sub-class of the Thief in Advanced Dungeons & Dragons 1st Edition (AD&D1e).

Where the Thief focuses on taking scores and pursuit of professional esteem, the Assassin uses the same skillset for the specific end of murder. They are, by necessity, always Evil in Alignment and their extensive trainnig is abstracted into its Ability Score requirements and starting age for fresh 1st level characters.

What makes the Assassin notable is that, in return for delayed Thief Skill development (with the exception of Backstab), they gain the explicit ability to earn Experience Points by performing Assassination missions- including during downtime. (PHB p. 29)

They also may use any weapon and shield, giving them a slight edge on Thieves (PHB p. 28) and are not only allowed to use poison but are expected to do so (p. 29).

The Assassin, therefore is exactly what the name says: a specialist in targetted killing of defenseless marks. What motivates him may be religion, or it may be something more ordinary, but he nonetheless is a man of wicked character that underwent specific training to be able to do this and the class's structure makes this clear.

One does not just wake up one day, decide to gank people for gold, and be able to speak the Alignment languages of those other than one's own. (ibid) While the Thief seeks to be a Grey Man specifically to blend in and be ignored, the Assassin is an explicit master of disguise (ibid). This too points to the Assassin being a trained killer, not a just a variety of Thief.

The Assassin's secretive nature includes operational security, such that he cannot retain hirelings until 4th level (and then, only other Assassins); at 8th he may retain Thieves also, and all restrictions are lifted at 12th (p. 30).

The Assassin, like the Druid and the Monk, has limited numbers of high-level members, though the competition doesn't start until the Assassin reaches 13th level. 14th (Guildmaster) and 15th (Grandfather) are limited occupancy; you have to kill the incumbent to take the spot (ibid). This provision clarifies what, up to this point, was implied: the Assassin was formally trained in his craft, and usually is a member of such an organization.

What it is not, however, is an ordinary crime family or similar syndicate. The Assassin specializes in murder for hire, with spying being the prelude to the kill, so even a Chaotic Evil Assassin has that organization to ground his activities. As the name implies, the best real world example is the Order of Assassins- the same real world source for Ubisoft's Assassin's Creed series.

How then to play the Assassin?

Like the Thief, the Assassin is not a glory-seeker as such. Rather than professional esteem among criminal society, the Assassin seeks the acclaim of his peers- ultimately in the form of becoming Grandfather of Assassins, a form of apotheosis for his ilk, around which legends shall be told even to outsiders.

The Assassin, like the Thief, exists in a parallel society. Moreso than the Thief, as the Assassin likely hides from other (non-Assassin) criminals what he really is. As the Thief sheds guises to maintain concealment from the law, the Assassins dons guises to approach targets and await the moment to strike.

He need not necessarily slip silently into reach; a solid disguise that gets him close enough is sufficient to maintain Surprise over the mark, and with it the privledge to autokill the target on the Assassination Table (DMG p. 75)- something that need not even require the use of a formal weapon, at the Referee's discretion. Making the most of this table is what everything else the Assassin can do is about, as it is all about optimizing one's odds for success.

How then to play the Assassin?

Like the Thief, the Assassin has a goal- and usually that is a mission, as lower-level Assassins are often in thrall to senior members. His ability to use Thief abilities, especially from 3rd level on, allows him to pass as one. In his secondary role as a spy, he could be a long-term first contact man sent into an area to assess the threats in the area and recommend courses of action to his superiors.

Or he's truly independent, and this area is one he is willing to play the long game by building this area up to become his base for his Guild- and deal with the Grandfather when he's ready.

The Assassin's tell is his preoccupation with security; being one who trained to penetrate defenses literal and metaphorical specifically to kill people, he's going to show that awareness subconsciously in his behavior- back to the wall, always tracking exits, never getting too close to anyone, dagger under the pillow, and so on. He has no problems using assumed names, lying to people, fabricating entire histories (and forging the evidence to support them), and pretending to be what he is not; in time, such practices become second-nature and his deceptions refined to the point where magic is necessary to tell that he is lying.

Over the course of his levelling, the Assassin will go from a solo operator to a team leader to a guildmaster- eventually to command all Assassins (and put hits out on those that resist him). From 47 to Hunt to Old Man Ezio, and if he is wise he will never let anyone know what he really is until it's too late to stop him.

Not that most would. He is the blade in the dark, and you are his latest contract.