12 KiB
Harkonnen Nexus: source and implementation contract
Source audit, 10 September 2026. This is a rules contract, not a runtime completion claim. The common Nexus lifecycle and existing expansion release gates still apply. The pending reaction-privacy question remains unresolved; this audit does not authorize a Betrayal reaction policy.
Primary authority
- The original printed Nexus components: the Harkonnen face was freshly inspected in the previously acquired 3024×4032 photograph,
/tmp/dune-nexus-cards.jpg. Its three panels establish the effects below. The photographed publisher text is the authority, not the uploader's commentary. - GF9 Ecaz & Moritani, pp.11 and 16: common modes, card disposal and the explicit Tleilaxu/Harkonnen Secret Ally FAQ. Fresh official indexed text and the previously acquired publisher-authored PDF mirror were inspected; direct official retrieval returned 403. Acquisition details are in the common contract.
- GF9 base rules, pp.11 and 17: traitor revelation and battle consequences, Harkonnen's four starting traitors and allied use. GF9 quick-start, p.4 establishes the participating-faction deck and return of unselected setup cards.
- GF9 Ixians & Tleilaxu, pp.4, 6–7 and Karama table: shared Traitor Deck, three Face Dancers, reveal/replacement cycle and ordinary Mentat replacement. GF9 CHOAM & Richese, p.12 supplies the related Rihani Decipherer ruling.
- GF9 November 2020 FAQ, pp.3, 7–8: retained traitor identities after revival, Karama boundaries, unused-card privacy and Truthtrance. Fresh publisher-indexed text was retrieved. The earlier April FAQ was encountered but is not used to override November's cancellation rules.
Printed effects
| Mode | Eligibility and timing | Physical operation |
|---|---|---|
| Cunning | Harkonnen holds its own Nexus card; at any time. | Draw one Traitor Card into the hand, then secretly select any one held Traitor Card and shuffle it into the Traitor Deck. |
| Secret Ally | Harkonnen is absent; during Mentat Pause. | Draw two Traitor Cards into the hand, then select two held Traitor Cards and shuffle them into the Traitor Deck. |
| Betrayal | Another player controls Harkonnen; a Harkonnen traitor has been revealed. | Cancel that traitor, shuffle its card into the Traitor Deck, and give Harkonnen a replacement draw during Mentat Pause. |
These are mandatory draw/return counts once played. Newly drawn identities are in the hand before selection, so they may be returned. Neither exchange permanently increases hand size. The card does not restrict returns to newly drawn cards or currently living leaders. Betrayal's replacement is delayed, whereas returning its canceled identity is immediate. Printed Harkonnen face
The common rules make these modes mutually exclusive and consume the Nexus card on play. Secret Ally does not create a formal alliance. The E3 FAQ expressly classifies Tleilaxu's retained card as a Face Dancer. It does not describe return eligibility for already revealed dancers. E3, pp.11,16
Supported composition and implementation requirements
Exchange transaction. Keep one immutable draw receipt containing the original owner, mode, turn/phase and physical draw group. Suspend the original continuation while the owner chooses exactly the required number of distinct currently held identities. Bind the return to that event; complete custody transfer, shuffle and resume once. Reconnects and retries must not redraw. There is a real choice after the draw, so this pending choice is necessary; no additional acknowledgement is needed afterward. This is implementation composition of the printed sequence.
Private custody. Project drawn cards and return options only to the holder. Other seats may see the publicly played Nexus mode and a pending exchange, but not the drawn, returned or remaining identities, deck order, or whether a drawn card matched a combatant. Do not treat a previously exposed ordinary traitor as discarded: the November FAQ says that identity remains a traitor after its leader dies and revives. It also prohibits retaining unused Traitor Cards as reference material. An old private inspection receipt is a historical observation, not proof of current custody. November FAQ, pp.3,8
Battle cancellation. Bind Betrayal to the actual revealed identity and Harkonnen caller before committing the traitor outcome. Base rules give a called traitor victory and specific casualty/spice consequences; a double call has a different outcome. Cancellation must therefore remove the targeted call and resolve the surviving situation once, not refund an already resolved battle. Harkonnen can call on an ally's behalf, so an implementation must retain caller and beneficiary separately. Base rules, pp.11,17
Deck inventory. Draw from the existing physical reserve, not from current leader discs: capture, gholas and death do not manufacture Traitor Cards. Setup removes absent factions and returns unselected identities; Tleilaxu draws its three from that shared deck afterward. Quick-start p.4, E1 pp.4,6
Setup order follow-up. Fresh inspection of base p.6 confirms that unchosen setup cards return face down to the bottom of the Traitor Deck. Quick-start p.4 agrees. E1 p.6 adds a shuffle after those returns specifically before Tleilaxu draws its initial three. Neither E3's common Nexus rules nor the Harkonnen face orders an additional setup shuffle or a shuffle before its initial exchange draw. Preserve the existing non-Tleilaxu reserve order in fresh and legacy rooms; append actual unchosen cards at setup, then draw from that saved reserve. There is no source basis for a corrective reshuffle migration. The physical order of simultaneous players' setup returns is not separately specified; serialized return order does not justify adding a shuffle. Base p.6, Quick-start p.4, E1 p.6
No retrieved rule supplies an empty-Traitor-Deck fallback. For the ordinary supported setup this is not an expected shortage: with n >= 3 five-leader factions, held cards total n + 3H + 2T, where H and T indicate Harkonnen and Tleilaxu. The smallest resulting reserve is seven. These exchanges have zero net growth; Betrayal temporarily increases reserve size. This arithmetic is a bounded inventory argument, not a rule for other variants. Reject undersized/inconsistent custody before spending the Nexus card; never recycle another player's held cards or silently draw fewer.
Tleilaxu and shared-deck boundaries
E1 distinguishes two operations: after all three dancers reveal, return all three, shuffle and draw three; during Mentat, optionally return one unrevealed dancer, shuffle and draw one. Revealed dancers ordinarily stay until the full cycle completes. Its Karama table permits stopping ordinary Mentat replacement but excludes other Face Dancer effects. Harkonnen traitor revelation itself is not an ordinary Karama target. These specific entries do not establish blanket Nexus immunity. E1 p.7 and Karama table
The Rihani Decipherer FAQ classifies its acquired identity as a Face Dancer and explicitly restricts replacement to an unrevealed dancer. This is relevant evidence for preserving revealed custody, but is a ruling for that skill. The Harkonnen Nexus FAQ states only the resulting card type. Compose it with E1's existing restriction: return options include newly drawn cards and existing unrevealed dancers; preserve prior revealed dancers. The two new cards guarantee at least two valid return choices, so this supports the full exchange rather than blocking Tleilaxu from playing it. No inspected passage explicitly classifies revealed dancers as being outside a player's hand; the justification is their protected revealed status. E2 p.12, E3 p.16
Timing composition
Cunning's anytime permission supports play off turn and after battle plans reveal. Before a traitor declaration, the resulting held identities determine whether Harkonnen can call. After a declaration, preserve the committed call and its original physical identity independently of subsequent hand changes. An exchange changes custody; it does not contain Betrayal's explicit cancellation instruction. A declared identity returned through Cunning therefore must not retract the call or make its original declaration fail retroactive validation. This is composition of the printed effects with an immutable digital declaration, not a separate publisher FAQ about sealed requests.
During Mentat, Tleilaxu can select the order of its own ordinary cycling and Secret Ally exchange. Complete each operation before another deck action begins; do not interleave another draw between Secret Ally's two-card draw and return. No inspected source imposes a priority between these two optional actions. This player-controlled sequencing avoids silently fixing a priority in the phase serializer. It does not resolve competing mandatory draws belonging to different players.
Material unresolved timing
- No retrieved primary ruling orders Betrayal's Mentat replacement against Tleilaxu's ordinary cycling or other Traitor Deck consumers. Those shuffles can change the next identity drawn. Do not describe a chosen serializer as publisher-mandated priority. Secret Ally and Betrayal themselves cannot compete: they require opposite faction-presence states and use the same unique Nexus card.
- Likewise, the sources do not establish arbitrary interruption of another player's owned decision or reversal of a completed battle. A full anytime implementation must specify continuation ownership and interaction with existing Truthtrance promises without releasing those promises merely to make an exchange legal.
- The existing unanswered reaction-privacy question still blocks choosing a Betrayal window policy. Do not repeat that question or infer an answer from this audit. Ordinary victory/end-turn advancement must not silently erase a pending Mentat exchange or an earned replacement obligation.
Focused verification should cover draw-before-return (including returning new cards), zero net hand growth, actual Tleilaxu custody, every-seat privacy, exact restoration of suspended decisions, immutable rejection, and once-only saved shuffle/replacement receipts. These checks do not certify all Nexus effects or expansion combinations.