SpaceChem Bench: Moustachium 604

tf2_2 Medium Bonding & routing Single-reactor Australia! · SpaceChem Bench report →

Inputs: α Australium (Av), β Australium (Av). Output: ψ Moustachium 604 (Av4) ×10. Features: Bonders (4).

In SpaceChem Bench, 16 LLMs each had one attempt at this SpaceChem puzzle, with 40 minutes to build a working solution and keep optimizing it, without seeing the community archive. 12 of 16 models solved it. Together they found 2 new Pareto-frontier points beyond the frozen community archive.

12 / 16models solved it
77best LLM cycles (63 community)
2new frontier points

Records

ScoreCommunity bestBest LLMModel
Cycles6377GPT-6 Astra · +22%
Reactors11DeepSeek V4.1 Flash Ties record
Symbols99Fable 5.1 Ties record

Community records from the community archive when we froze it on October 18, 2026. A point counts only after fresh-game replay and SChem’s precognition check.

Pareto frontier

Pareto explorer

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Community archiveModel frontier pointNew frontier point
Select a point with the mouse or keyboard to inspect its scores and reactor blueprint.

Search over time

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Every model

ModelSolvedBest cyclesBest reactorsBest symbolsNew frontier points
01GPT-6 AstraYes771101
02Gemini 4 ArgonYes164191
03Opus 5.5Yes92112—
04Sonnet 5.5Yes102112—
05GPT-6.1 SolYes125114—
06Fable 5.1Yes16419—
07Muse Wonder 1.0Yes295135—
08Haiku 5.5Yes312136—
09DeepSeek V4.1 FlashYes319133—
10Grok 4.7Yes354133—
11Kimi K3.1 ProYes359133—
12Gemini 3.8 FlashYes397120—
13GLM-5.3No————
14GPT-6 LunaNo————
15MiMo-V2.6-ProNo————
16Muse Spark 1.3No————

Best scores can come from different solutions. New frontier points are not matched or beaten on all three scores by any community solution.

Best model solutions

These solutions are in SpaceChem Community Edition export format and released under the MIT License. All of this puzzle’s model solutions are on GitHub and Hugging Face.

GPT-6 Astra Fewest cyclesFewest reactors

77 cycles · 1 reactor · 32 symbolstf2_2.77-1-32.txt on GitHub

Layout

α β ψ ω 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 ↓ → ← ↑ ↓ → ← ↑ S← S↑ IN α IN α GRAB GRAB IN α OUT ψ IN α B+ IN α B+ IN α B+ IN α B+ IN α B+ OUT ψ B+ B+ B+ DROP DROP CCW CCW

Running in the game

GPT-6 Astra solution running on tf2_2 in SpaceChem
SpaceChem Community Edition export (tf2_2.77-1-32.txt)
SOLUTION:Moustachium 604,Player,0-0-0
COMPONENT:'drag-starter-reactor',2,0,''
MEMBER:'instr-start',180,0,128,7,0,0,0
MEMBER:'instr-start',-90,0,32,0,2,0,0
MEMBER:'feature-bonder',-1,0,1,1,1,0,0
MEMBER:'feature-bonder',-1,0,1,2,1,0,0
MEMBER:'feature-bonder',-1,0,1,3,1,0,0
MEMBER:'feature-bonder',-1,0,1,0,7,0,0
MEMBER:'instr-arrow',90,0,64,0,0,0,0
MEMBER:'instr-arrow',0,0,64,0,1,0,0
MEMBER:'instr-arrow',180,0,64,6,0,0,0
MEMBER:'instr-arrow',-90,0,64,6,1,0,0
MEMBER:'instr-input',-1,0,128,0,1,0,0
MEMBER:'instr-grab',-1,1,128,1,1,0,0
MEMBER:'instr-input',-1,0,128,2,0,0,0
MEMBER:'instr-input',-1,0,128,2,1,0,0
MEMBER:'instr-input',-1,0,128,3,0,0,0
MEMBER:'instr-input',-1,0,128,3,1,0,0
MEMBER:'instr-input',-1,0,128,4,0,0,0
MEMBER:'instr-input',-1,0,128,4,1,0,0
MEMBER:'instr-output',-1,0,128,5,0,0,0
MEMBER:'instr-bond',-1,0,128,5,1,0,0
MEMBER:'instr-grab',-1,2,128,6,0,0,0
MEMBER:'instr-rotate',-1,1,128,6,1,0,0
MEMBER:'instr-arrow',90,0,16,0,0,0,0
MEMBER:'instr-arrow',0,0,16,0,1,0,0
MEMBER:'instr-arrow',180,0,16,6,0,0,0
MEMBER:'instr-arrow',-90,0,16,6,1,0,0
MEMBER:'instr-input',-1,0,32,0,1,0,0
MEMBER:'instr-grab',-1,1,32,1,1,0,0
MEMBER:'instr-output',-1,0,32,2,0,0,0
MEMBER:'instr-bond',-1,0,32,2,1,0,0
MEMBER:'instr-bond',-1,0,32,3,0,0,0
MEMBER:'instr-bond',-1,0,32,3,1,0,0
MEMBER:'instr-bond',-1,0,32,4,0,0,0
MEMBER:'instr-bond',-1,0,32,4,1,0,0
MEMBER:'instr-bond',-1,0,32,5,0,0,0
MEMBER:'instr-bond',-1,0,32,5,1,0,0
MEMBER:'instr-grab',-1,2,32,6,0,0,0
MEMBER:'instr-rotate',-1,1,32,6,1,0,0

Fable 5.1 Fewest symbols

713 cycles · 1 reactor · 9 symbolstf2_2.713-1-9.txt on GitHub

Layout

α β ψ ω 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 → ← S↓ S← IN α GRAB DROP GRAB OUT ψ DROP B+

Running in the game

Fable 5.1 solution running on tf2_2 in SpaceChem
SpaceChem Community Edition export (tf2_2.713-1-9.txt)
SOLUTION:Moustachium 604,Player,0-0-0
COMPONENT:'drag-starter-reactor',2,0,''
MEMBER:'instr-start',90,0,128,0,0,0,0
MEMBER:'instr-start',180,0,32,1,7,0,0
MEMBER:'feature-bonder',-1,0,1,1,1,0,0
MEMBER:'feature-bonder',-1,0,1,2,1,0,0
MEMBER:'feature-bonder',-1,0,1,0,7,0,0
MEMBER:'feature-bonder',-1,0,1,2,7,0,0
MEMBER:'instr-arrow',0,0,64,0,1,0,0
MEMBER:'instr-arrow',180,0,64,9,1,0,0
MEMBER:'instr-input',-1,0,128,0,1,0,0
MEMBER:'instr-grab',-1,1,128,1,1,0,0
MEMBER:'instr-grab',-1,2,128,2,1,0,0
MEMBER:'instr-grab',-1,1,128,5,1,0,0
MEMBER:'instr-output',-1,0,128,8,1,0,0
MEMBER:'instr-grab',-1,2,128,9,1,0,0
MEMBER:'instr-bond',-1,0,32,0,7,0,0