DeepSeek’s Rubik’s Cube Demo Fails to Scramble and Solve Correctly

Matthew Berman examines a cube simulation generated with DeepSeek V4.1 Flash through the Codex harness.

MBMatthew BermanHost · Forward Future
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Matthew Berman
Published
Sep 12, 2026
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0:32
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1 min
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SUMMARY

In 30 seconds

In this short demonstration, Berman says the generated cube’s pieces appear disconnected, colors change during scrambling without corresponding movement, and the solve attempt fails. The clip shows one result rather than a comprehensive model evaluation.

  1. 1The setupThe model runs through the Codex harness.
  2. 2Disconnected piecesThe individual squares appear to float independently.
  3. 3Scramble and solveBerman observes colors changing without matching movement and an unsuccessful solve.

Takeaways

  1. The demonstration uses DeepSeek V4.1 Flash through the Codex harness.
  2. Berman observes apparent independent pieces and color changes during scrambling.
  3. The shown solve attempt does not produce a solved cube.
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01

Inspecting the cube

Berman identifies apparent problems with the simulated pieces.

I show a Rubik’s Cube simulation made using DeepSeek V4.1 Flash through the Codex harness. Looking closely, the squares seem to float independently instead of behaving as connected cube pieces.

02

Scramble and solve

He demonstrates color changes and an unsuccessful solve.

Scrambled cube simulation
SLIDE 1 / 1Scrambled cube simulationThe demo shows the cube after a scramble; Berman observes that colors change without matching piece movement.

When I scramble the cube, I observe face colors changing without corresponding movement. The subsequent solve attempt does not solve the cube. This is one brief demonstration, not a comprehensive comparison of models.

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