Roles

Different roles are assigned to all characters in a given loop of Gnosia. Each role has different capabilities and purposes, enlivening the game and allowing for each loop to be a unique experience. The player can select which roles are present in a given loop and may even choose their own role, but NPCs will be assigned their role randomly per loop. Event Search might slot a character into a specific role to help you obtain certain Notes, but you won't be aware of who's what beforehand.

Trying out different roles is essential for uncovering all of the Notes and completing the game - and what fun would it be if you never branched out, anyway?

Crew Member
Crew Member is the "default" role. They're the "villagers" of the game: just a bunch of plain old humans. Crew Members don't have any special actions and cannot lie.

Gnosia
The Gnosia are the primary enemy role in the game. If they come to equal or outnumber the number of humans, they win. At night the Gnosia will select one character to attempt to eliminate. If the player is Gnosia they will always get to make the selection themself, but any fellow Gnosia may give suggestions on who to pick. Gnosia cannot eliminate each other (though they can certainly throw each other under the bus during debates if needed), and if they choose to eliminate the Bug or someone protected by the Guardian Angel their attempt will fail.

Gnosia are capable of lying about their roles and pretending to be an Engineer or Doctor instead, provided a genuine Engineer/Doctor is also present. Almost anything the Gnosia say will be considered a lie, so it's essential for the player to raise their Performance ability to be able lie effectively.

Gnosia can only be eliminated by putting them into cold sleep, and thus the goal of each discussion phase is for the humans to successfully guess who's Gnosia.

Engineer
The Engineer is a human who is capable of using the ship's research equipment to analyze the dimensional waves of a target of their choosing each night. In other words, the Engineer has the power to check if someone is human or Gnosia. If the Engineer chooses to investigate someone who turns out to have been the Bug, the report will come back as human but the Bug will be eliminated.

Lying roles can claim to be the Engineer, so analyzing the differences in Engineer Reports is critical in defining who's the real Engineer and who's a saboteur. Players playing as a fake Engineer need to be careful, as declaring too many people Gnosia or accidentally pretending to investigate the Bug and not having them disappear can lead to the player being labeled as a Definite Enemy.

If the player is the Engineer and someone falsely claims that they're the engineer, it's important that they reveal their role immediately. If not... bad things might happen.

Doctor
The Doctor is a human who examines the bodies of those put into cold sleep the previous day to determine if they were human or Gnosia. This strictly determines whether the person put into cold sleep was Gnosia or not; the Doctor cannot tell if a human put into cold sleep was a Bug, for instance.

Like Engineer, the role of Doctor can be fake claimed by lying roles. It is thus imperative for the player to reveal their role as Doctor if they are one and a fake steps forward, lest the game get confused and let the AI lead it into a paradox.

Guardian Angel
Guardian Angels are a human role that cannot be claimed, as the group recognizes that doing so would make them an immediate target. This is because the Guardian Angel has the ability to delay the time of warp, keeping the Gnosia from attacking their intended victim. However, the Guardian Angel can only delay the warp for a short time and thus are only capable of protecting one person.

The Guardian Angel cannot protect themself and is not made aware of anyone's roles. There are otherwise no restrictions on who they can protect, so they may choose to protect the same person repeatedly. Different characters have different preferences for who they choose to protect; Sha-Ming, for instance, exclusively protects female characters until the point where there are none left.

If the Guardian Angel protects someone who's attacked by the Gnosia, no one will be eliminated by them that night. The Gnosia will not receive any special notification about this, so if the Bug is still in play they won't have any way of knowing if the person they attacked was protected or simply just the Bug.

Guard Duty
The Guards are two guaranteed humans who were on the ship before it reached Liu-An and picked up the other characters. Those on Guard Duty can vouch for the fact that the other never left the ship and thus cannot possibly be Gnosia. This makes it a unique role in that both Guards must claim the role at once and - while the role cannot be fake claimed and the AI will never do this - a Guard who steps forward could be left hanging if the player doesn't claim as well.

If both Guards don't step forward at the same time - such as if one of them was put into cold sleep/eliminated before they were asked or if the player is causing problems on purpose - the role cannot be claimed and the Guards will be treated like anyone else, capable of being suspected and put into cold sleep.

If the Guards claim as normal, however, they will be treated as Definite Humans and will no longer be suspected during the debates. This helps give their opinions more value but also leaves them at risk of being eliminated by the Gnosia. Guards are high priority targets; their nature as Definite Humans means it's dangerous to let them live late into the game since they can't be put into cold sleep, leaving the Gnosia at risk of being identified as Definite Enemies in the lategame and overall making their job harder. Should someone the player wants to keep around end up on Guard Duty, their only option is to hope they're playing as Guardian Angel or Gnosia themself; otherwise, their only hope is that someone else draws more attention.

If the player ends up on Guard Duty, however, they have more options. High Stealth will be critical, and if their Stealth is at 10 or higher unlocking the skill Small Talk will be critical. Using Small Talk once per day will often be all the player needs to avoid getting eliminated at night, at least up until the point in a loop where they're the only practical victim left. Even then, if the Guardian Angel is around they might recognize this and help keep them alive.

AC Follower
AC Follower stands for Anti-Cosmic Follower; followers of Gnos who are humans on the side of Gnosia. The AC Follower can only win if they survive to see the Gnosia take over the ship and are capable of lying to achieve this goal. However, the AC Follower does not know who the Gnosia are and the Gnosia are not made aware of who the AC Follower is. This makes it a challenging role to succeed at, as even if the player is able to successfully identify the Gnosia the Gnosia might still end up eliminating them without having ever known they were on the same side. This difficulty makes AC Follower the role that typically will give the player the most EXP for winning as.

Succeeding at playing AC Follower requires some risk. The most critical part of success is getting the Gnosia to recognize that you're on their side. Fake claiming a role is a good way to do this, as forging a report in which someone you know to be Gnosia is declared human will alert them to the fact that you're lying. Of course, this risks revealing that you're a liar, so a high Performance stat is essential for pulling this off. On the plus side, though, if at least one of the Gnosia have high Intuition but the remaining humans don't, it's possibly that your lies will help the Gnosia recognize you without tipping off any of the humans.

In any case, any strategy for succeeding as AC Follower generally requires identifying the Gnosia first, which can already be tricky even as a normal human. High Intuition can help with this a bit, but otherwise you'll simply have to watch out for patterns and odd behavior. Once you've done that and got them to recognize you, though, you're still not in the clear. While the Gnosia will typically try to keep someone they know to be the AC Follower around, ultimate the AC Follower is a tool for them to use. If the humans identify the AC Follower as an enemy or the Gnosia have no other options for a human to eliminate without exposing themselves in some way then the Gnosia won't hesitate to off them. Even though doing so can help guarantee the Gnosia a win and thus be a technical success for the AC Follower, the game still counts any death as a loss.

Bug
The Bug, while technically considered human, is something else entirely. The Bug is a "cosmic mistake", a sort of glitch in the universe, that will end the universe if they survive until the end of the loop. Regardless of whether it's the humans or Gnosia who win, the Bug will be the true winner of any loop they survive. Of course, upon doing so the universe will promptly end. This makes the Bug an important target to eliminate, as if you aren't playing as the Bug yourself any chance of victory will be ruined by them.

Getting rid of the Bug isn't particularly easy. The Bug can lie and fake claim roles, but you catching them in a lie could just be identifying them as an AC Follower or Gnosia. The Gnosia don't have it much easier than the humans: if they attempt to eliminate the Bug overnight, their attempt will fail. If no Guardian Angel is in play this will immediately identify the Bug for them, but if the Guardian Angel is in play they won't be able to tell if their attack failed because their target was the Bug or because their target was protected.

The best weapon against the Bug is the Engineer. If the Engineer investigates the Bug overnight then the Bug will vanish: as entities that "don't exist", attempting to thoroughly analyze them will cause the Bug to harmlessly blip out of existence. The Engineer's priority should thus be finding the Bug, while the Gnosia/AC Follower should be careful not to pretend to analyze the Bug; if a fake Engineer analyzes the Bug and the Bug is later eliminated by the Engineer, depending on the setup it may create a situation where the fake Engineer can be labeled as a Definite Enemy.

Things get trickier if no Engineer is around. With the Gnosia incapable of eliminating the Bug themselves, cold sleep is the only way to eliminate a Bug. If the Bug has fake claimed a role it gets easier to narrow things down, but if not the player will just have to hope they and the other characters note someone acting suspicious in time.

If the player is playing as a Bug themself, the smartest thing to do is to avoid claiming a role and to stay in the background, maintaining their Hate levels carefully to avoid suspicion and to avoid being attacked by the Gnosia and revealed as a potential Bug (guaranteed Bug if the Guardian Angel is not in play). Not only would claiming a role allow for their lies to be spotted, but depending on the roster for that loop the number of Engineer/Doctor claims may immediately indicate the Bug is among them, leaving them as likely subjects for debate and even more likely targets for the real Engineer. If the player wants to fake claim anyway, their priorities should be getting rid of the real Engineer (if applicable), either convincing the humans that they're the real Engineer/Doctor or convincing the Gnosia that they're the AC Follower (if applicable), and figuring out which side would be easier to survive on.