The player has to choose a faction, giving him unique game mechanics and perks with some drawbacks. There are 3 factions to choose from, with the ability to choose not to be a part of a faction.
Being a part of the faction not only gives new mechanics, but also a new skill tree and stats to improve.
They are focused on the explorer playstyle, where the player explores new areas out of curiosity and wonder. Their unique mechanic is the Map system, which allows the player to orient around the backrooms, put waypoints, mark and find points of interest and evade danger.
Via the Skill system you can improve how far you can see in your map, what things you can do in your map, as well as get new UI elements like an arbitrary compass and a full blown Minimap
They are focused on the survival game playstyle, that is heavily leaning into its primary mechanic - Crafting [OLD] . All of the crafting is done in a Workshop, which can also be used if the player is not a Firefly as a shop, where the player can order something to be crafted by another firefly, which usually comes to a higher cost. Most stuff that a Firefly player can craft cannot be acquired by a non Firefly player via the Workshop.
Crafting allows not only to create new weapons instead of buying/finding ones, but also upgrade them. It also allows the creation of gadgets that do the same tasks from the other factions, like a radar for detecting entities, a manual compass that points away from the Nexus and paint cans for drawing on walls to orient around the Backrooms.
Via the Skill system you can improve your stats to unlock new recipes, like how precision you are with circuits, how strong you are with hitting the hammer, how heat resistant you are for forging
They are focused on the looter/roguelike playstyle that focuses a lot on stealth, speed and finding loot. The main game mechanic is Backrooms sense & Totems which allows to see certain things behind walls.
Using the Skill system you can improve how far you can see with your backrooms sense and how long it is active for, as well as stealth related skills like crouched speed, feather footsteps and holding your breath
The player can choose to not be a part of any faction and enter a “hardcore” mode, where the perks and benefits of any other faction are not present. The player also becomes part of a loose “faction” of rogues, exiles and bandits that are The Stranded.
The player however does get immediate access to new mechanics like the Black market, bandit squads, stealing carts from trade routes and other stuff that can create shenanigans between the existing factions.