Sherlogic Mystery
A storied logic puzzle from Mars. Read closely, every detail may matter.
Case File · Read Carefully
The Musk Haven Paradox
Musk Haven, Mars · 2135
Musk Haven was named in honor of the late Elon Musk, who advocated for the colonization of Mars. Now a permanent settlement, it depended on five autonomous robots: Atlas, Curie, Kepler, Nova, and Tesla. One maintained oxygen production, one handled water reclamation, one tended the greenhouse, one balanced the power grid, and one operated communications. Each worked that shift from a different station: Meridian Hub, Cobalt Vault, Helios Dome, Amber Gallery, or Zenith Spire. At 06:00 colony time, every receiver sounded an emergency tone.
A Message from Thursday
The transmission carried Musk Haven's own rotating identification codes and passed every authentication test. Its timestamp, however, was exactly 72 hours ahead. Static had destroyed most of the recording, but one sentence survived: “One autonomous unit will initiate a cascade ending all five colony services. Disable only that unit.” Chief Engineer Imani Rook refused to stop them all. Without oxygen, water, food, power, or communications, choosing the wrong robot could fulfill the warning by itself.
The Assignment Record
Rook opened the sealed shift roster. Curie was assigned to water reclamation, and Kepler to greenhouse and agriculture. Atlas had neither the water nor power assignment. Nova's orders involved neither oxygen production nor communications. A separate environmental entry showed that the oxygen unit had begun its shift in Meridian Hub.
The Location Log
Atlas's chassis beacon placed it in Meridian Hub, while Tesla's placed it in Zenith Spire. Curie had entered neither Helios Dome nor Amber Gallery, and Kepler had not entered Cobalt Vault. The power-balancing station for this shift was in Amber Gallery. No robot changed stations after the emergency message arrived.
Five Diagnostic Results
The automated check returned five different results: Sensor Drift, Valve Lag, Nominal, Directive Conflict, and Packet Echo. Kepler alone reported Nominal. The unit in Cobalt Vault reported Valve Lag, and the unit in Zenith Spire reported Packet Echo. Atlas did not report Directive Conflict. Rook noted that every robot was functioning exactly as its current programming required; none showed tampering or hostile intent.
The Surviving Fragments
A restoration pass recovered two fields from the future transmission: INITIATION SITE: AMBER GALLERY and LAST DIAGNOSTIC: DIRECTIVE CONFLICT. It also exposed the paradox. The emergency packet's future timestamp had caused the colony scheduler to queue its authenticated shelter command for exactly 72 hours later. At that moment, the power controller would obey one directive to reserve energy for radiation shelters and another to preserve life-support control buses. An outdated equipment table classified those same buses as ordinary service loads. The controller would therefore isolate them while correctly following both instructions as written. During the resulting collapse, Zenith Spire would automatically send the warning backward through an experimental relay. If Rook acted on that warning now, the collapse would never occur, and the message that saved Musk Haven would never be sent.
Detective’s note: There is no separate clue list. Circle the useful facts in your mind and transfer them to the grid.
Detective’s Deduction Grid
Record the relationships you uncover in the case file.
Eliminate is selected.
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