In a Mafia game, both the description of the character given to a player, and the ability of that character, are referred to as the player's "role". This is true when one is referring to both, and each separately. Furthermore, if a player is asked for a roleclaim, those doing the interrogating may be asking for an ability, or the player's actual role title.
Below is a list of roles and their basic descriptions.
It should be noted that the title of the roles below do not necessarily label the character that would have such a role. For example, while Otto from The Simpsons would be a literal bus driver, another character that could have a similar ability would be The Flash, the ability explained as the character running quickly between his targets, switching them as he went.
 List of Roles
If targeted by someone else at night [sometimes just for a kill] this player will instead kill that player, regardless of alignment or intent. It is also common for this player to be allowed to use their one-time passive kill actively, meaning instead of waiting to be targeted, they can choose a target of their own.
 Gun Owner
This player if,important,kill any player that targets them for any reason at night, unless specifically stated otherwise. They cannot choose who they kill.
This player will kill anyone that kills them at night or the person that puts the last vote on them in a lynch. Occasionally they will kill the first person to target them during a night phase, whether it is an investigative cop, a protecting doctor, any form of killer or anyone else for that matter, similar to an Army Veteran but without the option to be an active ability. Sometimes they can choose which player to kill when they are lynched. Occasionally a scum-role but generally a pro-town one.
This person is immune to night kills by the mafia but can sometimes be killed by a Serial Killer, depending on how the moderator sets up the game. Also, another variation is that the mafia can roleblock this player and target them for a kill both in the same night if they have those abilities in their crew and that can be used to get around their immunity.
This player can choose to switch any two players during the night phase by sending the moderator a private message with the names of the two players he wishes to switch. Whatever was originally supposed to happen to one will happen to the other, and if possible the two targets will use their abilities on the others chosen target.
A cop can investigate any player of his or her choosing at night and the moderator will send them the alignment of that player when the night phase ends. They can reveal that information however they wish, whether it be via an out-and-out role claim or by trying to steer suspicion toward or away from their target.
 Day Cop
This cop sends in their ability during the Day Phase, as opposed to during the Night Phase. They can find their results skewed in any way that another cop might.
 Flavor Cop
This cop will receive information on a players character (style of dress, weapon, anything that could be considered an outlying characteristic).
 Insane Cop
This cop always receives the wrong alignment for the person they investigate. Once they figure out that they are an insane cop, they can provide useful information by assuming the opposite of what they receive from the moderator is true.
 Mafia Cop
As mafia players already know who is mafia and who isn’t by virtue of being able to communicate with fellow mafia players, a mafia-aligned cop will receive information about the role of the person they choose to investigate.
 Naive Cop
A naive cop will always receive town-aligned results from an investigation, and are effectively useless.
 Paranoid Cop
A paranoid cop will always receive non-town aligned results from an investigation, and are effectively useless.
 Random Cop
This cop receives completely random information about the person they investigate, rendering them effectively useless.
 Role Cop
A role cop is a town-aligned cop that receives information on either a players role title (excluding alignment), or ability.
The cult leader, often called the cult recruiter, is the founding member of a cult, who has the job of recruiting new members. They cannot recruit certain people, including the mafia, and sometimes if they try to recruit a mafia member, they are killed but that is a variable decided by the moderator. If the leader is killed or lynched, the group can no longer recruit unless there is a secondary leader. The cult leader can communicate with members of their cult outside of the thread and win when their cult outnumbers the rest of the players. To recruit, the leader sends the name of the person they wish to recruit to the moderator. They find out if it was successful at the end of the night phase and the new member either joins immediately or at the end of the next night phase, at the moderator’s discretion.
 Secondary Cult Leader
A generic cult member unless the Cult Leader is killed, in which case they assume the role of leader and take over the responsibility of recruiting for the cult.
A cult member is, obviously, a member of a cult. Their objective is to recruit as many people as possible until they outnumber the rest of the players in the game. They can communicate with other members of their cult but have no special abilities, unless they had one before they were recruited.
A doctor can protect any player of their choosing during the night phase. This means that any attacks on that person will fail and the player will survive. Because of this, doctors are very important roles for the town. If two players target the protected player, the doctor only protects them from one attack and the other is successful.
A bodyguard will kill anyone that tries to attack the person they choose to protect.
 CPR Doctor
If the person they are protecting gets attacked, this doctor protects as normal. However, if they aren’t attacked, the doctor kills the player instead.
 Insane Doctor
There is a fifty-fifty chance that this doctor will kill the person they attempt to protect if they aren’t attacked by someone else. This is decided by the flip of a coin.
 Naïve Doctor
This doctor fails when they try to protect someone, and as such are completely useless.
 Paranoid Doctor
A paranoid doctor not only protects but also roleblocks their chosen player.
 Suicidal Doctor
This doctor takes the hit for the person they are trying to protect. If the person they choose to protect gets targeted for a kill, the doctor dies instead.
 Weak Doctor
If this doctor protects someone that is mafia-aligned or an individually aligned killer, they get killed. However, when protecting town-aligned players they are successful.
 Forensic Investigator
This townie has the ability to investigate dead bodies, to see either what they were killed with, what character they were killed by, or a list of players that may have potentially killed the townie. This last variation is most common, and as the forensic investigator examines more persons killed by a specific player, the list will grow progressively smaller.
The leader of a mafia group, they are responsible for sending in the night kill information to the moderator. They can communicate with their group outside of the thread to help decide who to kill each night before sending a private message with the name of their target and who is to carry out the kill to the moderator. Sometimes The Godfather will be allowed to recruit new members but doing so usually forgoes the night kill. If investigated by a Cop, The Godfather comes up town-aligned, though this can change either when one member of his crew is killed or all the other members are killed, depending on the moderator’s preference. If The Godfather is killed, the mafia lose their night kill for the next night while a new Godfather is chosen.
 Hated Townie
This townie requires one less vote than everyone else to be lynched.
 Jack of All Trades
This player has multiple abilities at his or her disposal, though most often, these abilities can only be used once per game. Typical abilities include, but are not limited to, silencing, killing, investigating, protecting, and roleblocking.
 Mafia Goon
A generic mafia member, who can be assigned to the night kill by The Godfather, game circumstances permitting. They have no special abilities but can communicate with other mafia members outside the thread.
 Mafia Hitman
Sometimes the mafia will have a designated hitman to carry out kills. They either choose their target themselves or The Godfather sends in the kill as usual but this character always carries it out. They can communicate with other mafia members outside of the thread. If the mafia hitman is killed, the mafia lose their night kill for the next night phase while they regroup and decide on a new killer.
Sometimes called a Politician, this player can change the lynch vote of any other player, regardless of whether they have voted or not. To do this they send the name of the player whose vote they wish to change and who they want them to vote for to the moderator. The also have their own vote, which they cast as normal in the thread. The moderator generally doesn’t show the manipulated vote in the vote counts.
A mason is part of a mason group that are town-aligned and can communicate outside of the thread. This has the added benefit of knowing some guaranteed allies as well as being able to discuss theories on who to lynch away from the view of mafia members.
 Recruiting Mason
Usually just starting with one player, this is essentially a town-aligned cult. They can recruit people at night by sending a private message to the moderator with the name of the person they wish to try and recruit. If they attempt to recruit a mafia-aligned player, they die.
A miller is a regular town player except that they come up mafia-aligned when investigated.
Rather than being able to switch someone else’s vote, this player can cast multiple votes on their own. Usually it is just two but can sometimes be three or even four in a large game.
 Popular Townie
This role is the opposite of the hated townie. It generally takes one extra vote to achieve a lynch on this person. However, sometime it can require more.
A psychiatrist’s goal is to find the Psychopath and cure him. They do this by sending a private message to the moderator at night with the name of the person they think is the psychopath. If they successfully find them, the psychopath is cured and becomes a regular townie. If not, the psychiatrist must continue to look.
More or less the same as a Psychiatrist, the firefighter is looking for the Arsonist instead of the Psychopath.
This player can choose to, for a set number of times per game although most often only once, revive a dead player. The player will in most cases maintain their role and role title as-was at the moment of death. The revived player then reaps the benefits (or consequences) of having every player in the game know his role title.
This player can block the night ability of any other player by sending a private message to the moderator with the name of the person they wish to block. Sometimes if they block the mafia Godfather they prevent the mafia from performing any actions at night, whether it be killing or recruiting. In other games they can block the designated mafia killer from carrying out their hit.
 Paranoid Bat Owner
This player will silence anyone that targets them for any reason at night. They cannot choose who they silence.
The mafia version of a Roleblocker.
A mafia member that can only roleblock a Bulletproof townie [or Army Veteran + variants] to allow a mafia kill on that player.
This player has the ability to target one player per night, although they won't know what action they will take until receiving their result PM the next morning. After the Schizophrenic chooses a target, the moderator will usually role a dice or use some other form of chance-driven mechanism to decide the Schizophrenic's effect on their target. This effect will usually vary between protecting, some sort of investigation, killing, silencing, and roleblocking. A schizophrenic is by no means limited to these abilities, and the number of effects a Schizophrenic may have on his or her target is also not set in stone.
A silencer is a player that choses somebody else to be silenced. They then are not allowed to talk for a specific time that varies moderator to moderator, though normal it's for that day phase. A silencer can be a Town or Mafia role.
 Serial Killer
A Serial Killer is individually aligned and their goal is to be the last remaining player in the game. They can perform one – usually mandatory – kill per night by sending the name of the player they wish to kill to the moderator. If they neglect to do so, they kill a random player if their kill is mandatory.
They are almost identical to a Serial Killer, except that they when there is a Psychopath in a game, there is always a Psychiatrist.
Usually they come in pairs, though could come in threes or more. When one dies, the other commits suicide the following night. They know who their sibling is but whether they can communicate outside of the thread is up to the moderator of each individual game. Occasionally one is town and one is mafia.
The same as siblings, except that sometimes the players don’t know who their lover is but could be given a searching ability at night to try and find them. The send a private message to the moderator with the name of the person they think is their lover and receive a message at the end of the night telling them if they were right or not. If they were right, they essentially assume the exact same role as a sibling.
 Treacherous Lover
This lover is a member of the mafia. They win with the mafia, regardless of whether their lover survives. However, when this player dies, their lover commits suicide like the normal lover relationship.
 Vengeful Lover
The same as a Vengeful Sibling but applied to the lover scenario.
 Vengeful Sibling
Instead of committing suicide when their sibling dies, vengeful siblings will become individually aligned upon the death of their sibling with the new goal of killing all of the people that killed their sibling. If it was via a lynch, the vengeful sibling must ensure all of those players are dead, at which point they win the game. If it was via night kill by the mafia, they must kill all members of the mafia, at which point they win the game. If it was via night kill by a town member, they must kill all members of the town. If it was via night kill by an individual, they must kill that individual, at which point they return to their normal role and win conditions. Players that must be killed being lynched or killed by other people counts towards the vengeful sibling achieving their win conditions.
This player silences their target, stopping them from participating in the thread. Sometime their target also loses their ability on the subsequent night as well.
A generic townie has no special abilities. The only use they have is to help discussion during the day phase and cast votes for lynches, along with surviving as part of the winning town group. Usually referred to as Vanilla.
A tracker is a variation of the Watcher role. Often times, they learn everybody that their target visited. However, sometimes, they only learn if their target was active.
A traitor is a mafia-aligned player that cannot communicate with the other mafia players outside of the thread, as they don’t know that they are aligned with them. The traitor knows the other mafia members and wins if the mafia wins. If mafia recruitment is allowed, they can be recruited at night and when they are, they become a normal mafia goon. If investigated, the traitor comes up town-aligned until they are recruited.
The vigilante is essentially just a town-aligned killer. They win with the town, so will try to only kill individuals and mafia members but they have no additional information so must figure out who to target by figuring out who they think are non-town aligned. They can abstain from killing each night if they choose to do so.
 Overeager Vigilante
The same as a regular vigilante except that they MUST kill every night; if they don’t send in a kill to the moderator, a random kill is assigned.
This player can choose one player to watch at night by sending their name to the moderator during the night phase. When the phase ends, the moderator will tell them who, if anybody, targeted that player during the night.