Chapter 4.4: The Synth and Companions
A Synthetic can share one body with you through your cysuit or travel beside you in a body of their own. The players decide how separate or integrated a Joined pair feels, how many names they use, and how the relationship appears in play. The rules offer a one-sheet default and a Companion option for two minds that need separate mechanics.
Note
What a synth is, in canon. Joining a Synthetic through a cysuit is a chosen, consent-gated, compatibility-gated bond. Integration depth grows through the relationship actually lived, and names remain the pair's choice. A synth needs no host to live, withdraws to any available compatible substrate if a body is lost, and rejoins only by choice. The Reference Manual carries the full account.
One Full Character, and Companions
Whatever the relationship, you have exactly one full character: one sheet, built the full way, and yours alone. That holds no matter which role you take. If you would rather play the synth than the body it rides in, the synth is your full character.
Anyone else who travels with you is a Companion: a synth partner, a colleague you call in, or a frame your cysuit prints. Build a Companion at supporting-character grade (Chapter 4.8). You run them in the scenes where they appear. One signature Companion is available without cost. Additional help uses Momentum under Chapter 4.8.
A synth is defined once, as a person: a name, what it is good at, the libraries it carries, what it cares about. Where that definition lands depends on the relationship.
| You want to play… | Players | Full character sheets | Companions you run |
|---|---|---|---|
| A Joined pair on one sheet | one | one: either the wearer or the Synthetic, including the pair's shared capabilities | none |
| Two independent minds sharing one body | one or two | one: either partner | the other, as the full character's signature Companion |
| Yourself, plus a partner with their own body | one | one: your pick, the body or the synth | the other, your signature Companion, fielded free |
| Two partners, side by side | two | two: a body each | none |
Joined: Sharing One Body
Most Joined characters use one character sheet. The pair may roleplay as two distinct people, a highly integrated consciousness, or any point between. Choose which person is the full character. That choice determines whose Values, Determination, offices, Mandates, Rite history, and personal advancement the sheet records; it says nothing about which mind matters more.
If the wearer is the full character, use the biological wearer's species package. If the Synthetic is the full character, use the Synthetic species package and add a character Trait naming the body they share, such as Joined in a Vyrkani Body or Joined in a Syliri Body. That Trait supplies the body's physiology, senses, vulnerabilities, and other species facts. The Synthetic Trait's immunity to biological conditions lapses while Joined. Build any capabilities the partnership has genuinely developed into the full character's six Focuses, four Values, Talents, and other Traits. Joining grants no extra slots by itself.
If the two minds need independent mechanics, build the partner who is not the full character as their signature Companion. The Companion keeps their own ratings, Focuses, Values, and Determination under the Companion rules. They occupy the same body and can Assist from inside shared awareness. The body still acts once. The Companion cannot take a separate physical turn, move to another zone, or operate the body as a second combatant.
With two players, one controls the full character and one controls the Companion. Each uses their own Momentum and the Determination recorded for the character they control. In ordinary scenes, either mind may lead a Task and the other may Assist when shared awareness contributes. In conflict, the shared body receives one turn. The players choose which mind leads its Major Action; the other may Assist under the normal action cost. Both may speak and make choices throughout the scene. Changing the lead changes no physical rating and grants no additional Action.
The shared body has one physical position, one Stress track, and one record of Injuries and physical Traits: those on the full character's sheet. When the Synthetic is the full character, their shared-body Trait establishes the biological fiction while their Fitness and derived Stress remain the ratings used in play. The Synthetic has no separate body that can be targeted. Poison, restraint, Prone, Injury, and other bodily effects constrain both minds through the one body.
Motor authority remains with the wearer. A sound cysuit resolves conflicting intentions in the wearer's favor, and joining gives the synth no unilateral power to override that guarantee. Voluntary handoffs and explicitly authorized Motor Authority use the consent rules in Chapter 3.5.
Individual Standing and the Rites
Citizenship, Starborn rank, offices, Mandates, and Rite history belong to one person. They never transfer automatically across a Joined pair. A Synthetic may undertake the Four Great Rites through the wearer's cysuit when both people consent to its use. The Rites assess the Synthetic candidate, and any resulting title belongs to the Synthetic alone. The wearer must pass separately to receive their own title.
Companion: A Partner with Their Own Body
A synth with their own body, a called-in colleague, a printed frame: each is a Companion who stands in the scene beside you. Your signature Companion is free in every scene. You run them yourself, either as the active character for the scene or in the narrower background role defined for Supporting Characters in Chapter 4.8. A Companion carries no Momentum of its own; any Momentum-fueled boost it uses draws on yours (Chapter 3.2).
To play the synth and travel with the body it once shared, make the synth your full character and the host a Companion you field and run.
Additional Help
Your signature Companion costs nothing in any scene. If it has a Value, it begins each commission with 1 Determination (Chapter 3.3).
Additional Supporting Characters enter through the Momentum rules in Chapter 4.8. They often come from the ship's ordinary crew, but the fiction may supply a local specialist, an established colleague, or another available person. Squads, allied ships, and other larger help use the same chapter's Bigger Help rule.
Your cysuit widens what you can print on your own, separately from either economy. With Engineering and the right material, you can print a helper on the spot: a simple drone is best handled as a scene Trait or an extra pair of hands, while a sophisticated frame is a Supporting Character and uses Chapter 4.8. Material, time, and suitable fabrication hardware are required; the standard cysuit fabricator covers only simple tools and small structures (Chapter 3.5).
When a Joined Wearer Dies
When a Joined wearer's body dies, the cysuit begins to dissolve and the Synthetic withdraws to an available compatible substrate. A ship, station, chassis, local system, or Matrix-01 can receive the transfer. The person who died cannot be recovered. The survivor remains the Synthetic, changed by the relationship and carrying memories and habits according to the partnership's depth.
If the Synthetic is the full character, they remain that full character after transfer: keep their Attributes, Specializations, Focuses, Values, Talents, Determination, offices, Mandates, and Rite history. Replace the shared-body Trait and interface Trait with Traits describing the compatible substrate that now houses them. No authority held by the deceased wearer transfers.
If the wearer was the full character, that character has died. A Synthetic Companion survives as the same Companion and may later be built as a replacement full character with the table's agreement. A later joining begins a new partnership; it does not create a new Synthetic person.