SpaceChem Bench: Puzzles
55 puzzles 19 easy · 10m 18 medium · 40m 18 hard · 60m · 
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All 55 SpaceChem puzzles from SpaceChem Bench: Can LLMs Beat Humans at 2D Spatial Programming?, with each puzzle’s difficulty, primary mechanic, chemical inputs and outputs, community archive cycle record, and the fastest of the 16 evaluated LLMs. Select any puzzle for its full records across cycles, reactors, and symbols, interactive Pareto explorer, search trajectories, and best model-written reactor blueprints and solution GIFs.
20new frontier points
11 / 55puzzles with new frontier points
11knock a community solution off the frontier
Difficulty
Mechanic
Single-reactor research puzzles 37
| Puzzle | Tier | Mechanic | Communitycycles | Best LLMcycles | Solvedmodels | Newpoints |
|---|---|---|---|---|---|---|
No Employment Record Found research_6 Random inputs: α Boron (B) / Aluminum (Al) / Silicon (Si), β Hydrogen (H). Output: ψ Hydrochloric Acid (HCl) ×20. | Hard | Fusion | 333 | 425GPT-6 Astra+1 | 12/16 | 3 |
Multiple Outputs research_tutorial_6 Inputs: α Carbon Monoxide (CO). Output: ψ Carbon (C) ×10, ω Oxygen (O) ×10. | Easy | Bonding & routing | 50 | 74GPT-6 Astra | 14/16 | — |
Crossover research_tutorial_1point5 Inputs: α Gold (Au), β Platinum (Pt). Output: ψ Platinum (Pt) ×10, ω Gold (Au) ×10. | Easy | Bonding & routing | 136 | 137GPT-6.1 Sol | 14/16 | — |
Random Oxides sensing_3 Random inputs: α Oxygen (O), β Zinc (Zn) / Titanium (Ti). Output: ψ Titanium Dioxide (TiO2) ×10, ω Zinc Oxide (ZnO) ×10. | Medium | Sensing | 176 | 278Opus 5.5 | 4/16 | — |
QT-3 quantum_3 Inputs: α Acetylene (C2H2). Output: ω Acetylene (C2H2) ×10. | Hard | Quantum tunnels | 161 | 226GPT-6.1 Sol | 7/16 | — |
Every Day is the First Day bonding_2 Inputs: α Hydrogen (H), β Carbon (C). Output: ψ Acetylene (C2H2) ×10. | Easy | Bonding & routing | 103 | 205GPT-6.1 Sol | 7/16 | — |
Best Left Unanswered research_tutorial_5 Inputs: α Nitrogen (N). Output: ψ Nitrogen (N2) ×10. | Easy | Bonding & routing | 42 | 64GPT-6 Astra | 13/16 | — |
QT-1 quantum_1 Inputs: α Helium (He). Output: ω Helium (He) ×10. | Medium | Quantum tunnels | 15 | 15GPT-6 Astra+11 | 16/16 | — |
Right All Along research_5 Inputs: α Carbon (C), β Fluorine (F). Output: ψ Polytetrafluoroethylene ((C2F4)n) ×10. | Hard | Sensing | 672 | 1,289GPT-6 Astra | 5/16 | 2 |
Double Bonds research_tutorial_4 Inputs: α Oxygen (O). Output: ψ Oxygen (O2) ×10. | Easy | Bonding & routing | 56 | 74GPT-6 Astra | 13/16 | — |
Split Before Bonding bonding_4 Inputs: α Hydrogen (H2), β Oxygen (O2). Output: ψ Hydrogen Peroxide (H2O2) ×10. | Easy | Bonding & routing | 73 | 83GPT-6.1 Sol | 9/16 | — |
Prelude to a Migraine sensing_2 Random inputs: α Oxygen (O) / Oxygen (O2). Output: ψ Oxygen (O) ×20. | Medium | Sensing | 67 | 67Gemini 4 Argon | 16/16 | 1 |
QT-2 quantum_2 Inputs: α Chlorine (Cl2). Output: ω Chlorine (Cl2) ×10. | Hard | Quantum tunnels | 80 | 80GPT-6 Astra+1 | 13/16 | — |
Unknown Sender fusion_3 Inputs: α Hydrogen (H). Output: ψ Neon (Ne) ×10. | Medium | Fusion | 124 | 126GPT-6.1 Sol | 13/16 | — |
Danger Zone mining_1 Random inputs: α Hydrogen (H) / Hydrogen (H2). Output: ψ Hydrogen (H2) ×20. | Medium | Sensing | 154 | 220Gemini 4 Argon | 14/16 | — |
No Stomach for Lunch research_3 Inputs: α Ethane (C2H6). Output: ψ Ethylene (C2H4) ×10, ω Hydrogen (H2) ×10. | Hard | Bonding & routing | 132 | 151Opus 5.5 | 9/16 | — |
Accidents Happen research_2 Random inputs: α Phosphorus (P) / Silicon (Si), β Hydrogen (H2). Output: ψ Phosphine (PH3) ×10, ω Silane (SiH4) ×10. | Hard | Sensing | 260 | 665GPT-6 Astra | 6/16 | — |
An Introduction to Bonding research_example_2 Inputs: α Silver (Ag), β Fluorine (F). Output: ψ Silver (I) Fluoride (AgF) ×10. | Easy | Bonding & routing | 74 | 75Gemini 4 Argon | 13/16 | — |
Slightly Different research_tutorial_1 Inputs: β Hydrogen (H2). Output: ω Hydrogen (H2) ×10. | Easy | Bonding & routing | 45 | 47GPT-6.1 Sol | 15/16 | 2 |
Like a Boss mining_2 Inputs: α Hydrogen (H), β Carbon (C). Output: ψ Methane (CH4) ×10. | Medium | Bonding & routing | 152 | 199Opus 5.5 | 9/16 | 1 |
An Introduction to Sensing sensing_1 Random inputs: α Neon (Ne) / Argon (Ar). Output: ψ Neon (Ne) ×10, ω Argon (Ar) ×10. | Medium | Sensing | 136 | 136Gemini 4 Argon | 16/16 | 2 |
I Told You So organic_3 Inputs: α Carbon (C), β Hydrogen (H). Output: ψ Benzene (C6H6) ×10. | Hard | Bonding & routing | 185 | 517Sonnet 5.5 | 7/16 | — |
Moustachium 608 tf2_3 Inputs: α Australium (Av), β Australium (Av). Output: ψ Moustachium 608 (Av8) ×10. | Hard | Bonding & routing | 156 | 865GPT-6.1 Sol | 3/16 | — |
It Takes Three bonding_3 Inputs: α Hydrogen (H), β Nitrogen (N). Output: ψ Ammonia (NH3) ×10. | Easy | Bonding & routing | 102 | 143GPT-6 Astra | 6/16 | — |
A Brief History of SpaceChem research_tutorial_2 Inputs: α Hydrogen (H), β Chlorine (Cl). Output: ω Hydrochloric Acid (HCl) ×10. | Easy | Bonding & routing | 75 | 75Gemini 4 Argon | 13/16 | — |
Under the Ice fusion_2 Inputs: α Hydrogen (H), β Nitrogen (N). Output: ψ Nitrous Oxide (N2O) ×10. | Medium | Fusion | 78 | 97Opus 5.5 | 10/16 | 2 |
Suspicious Behavior organic_2 Inputs: α Carbon (C), β Δ-Dihydrogen (ΔH2). Output: ψ Δ-Pseudopolyethylene ((Δ2C2H4)n) ×10. | Hard | Sensing | 1,101 | 2,415GPT-6.1 Sol | 3/16 | — |
Special Assignment organic_1 Inputs: α Ethylene (C2H4), β Hydroxyl Radical (OH). Output: ψ Ethanol (C2H5OH) ×10, ω Acetaldehyde (CH3CHO) ×10. | Hard | Bonding & routing | 193 | 406GPT-6 Astra | 8/16 | — |
Ice to Meet You fusion_1 Inputs: α Hydrogen (H), β Iron (II) Oxide (FeO). Output: ψ Cobalt (II) Oxide (CoO) ×10. | Medium | Fusion | 44 | 56GPT-6 Astra+1 | 16/16 | 1 |
The Plot Thickens mining_7 Inputs: α Carbon (C), β Hydrogen (H). Output: ψ Polyethylene ((C2H4)n) ×10. | Medium | Sensing | 419 | 468GPT-6.1 Sol | 9/16 | 3 |
The Blue Danube research_1 Random inputs: α Hydrogen (H) / Hydrogen (H2). Output: ψ Hydrogen (H2) ×20. | Hard | Sensing | 154 | 202Opus 5.5 | 16/16 | — |
Of Pancakes and Spaceships research_example_1 Inputs: α Oxygen (O2). Output: ψ Oxygen (O2) ×10. | Easy | Bonding & routing | 45 | 45GPT-6 Astra+1 | 16/16 | — |
Moustachium 604 tf2_2 Inputs: α Australium (Av), β Australium (Av). Output: ψ Moustachium 604 (Av4) ×10. | Medium | Bonding & routing | 63 | 77GPT-6 Astra | 12/16 | 2 |
QT-4 quantum_5 Inputs: α Methane (CH4), β Carbon (C). Output: ω Methane (CH4) ×10. | Hard | Quantum tunnels | 246 | 405GPT-6.1 Sol | 6/16 | 1 |
Moustachium 602 tf2_1 Inputs: α Australium (Av), β Australium (Av). Output: ψ Moustachium 602 (Av2) ×10. | Easy | Bonding & routing | 37 | 63GPT-6 Astra | 13/16 | — |
Removing Bonds research_tutorial_3 Inputs: α Fluorine (F2). Output: ψ Fluorine (F) ×10. | Easy | Bonding & routing | 27 | 27GPT-6 Astra | 15/16 | — |
Sacré Bleu! mining_3 Inputs: α Hydrogen Cyanide (HCN), β Methane (CH4). Output: ψ Hydrogen (H2) ×10, ω Acetonitrile (CH3CN) ×10. | Medium | Bonding & routing | 136 | 137Sonnet 5.5 | 13/16 | — |
Multi-reactor production puzzles 18
| Puzzle | Tier | Mechanic | Communitycycles | Best LLMcycles | Solvedmodels | Newpoints |
|---|---|---|---|---|---|---|
An Introduction to Pipelines production_tutorial_1 Inputs: α Benzene (C6H6), β Acetonitrile (CH3CN). Output: ψ Acetonitrile (CH3CN) ×10, ω Benzene (C6H6) ×10. | Easy | Multi-reactor production | 407 | 407GPT-6 Astra+4 | 16/16 | — |
No Ordinary Headache sensing_4 Random inputs: α Nitrogen (N2) / Oxygen (O2). Output: ψ Nitric Oxide (NO) ×10. | Medium | Multi-reactor production | 817 | 865GPT-6 Astra | 6/16 | — |
Challenge: Applied Fusion fusion_6 Inputs: α Water (H2O). Output: ψ Phosphoric Acid (H3PO4) ×10. | Medium | Multi-reactor production | 2,019 | 4,879GPT-6 Astra | 2/16 | — |
Ω-Pseudoethyne organic_5 Random inputs: α Carbomega (Ω / C), β Hydrogen (H2). Output: ψ Ω-Pseudoethyne (ΩH3CH) ×40. | Hard | Multi-reactor production | 839 | — | 0/16 | — |
No Thanks Necessary sensing_5 Random inputs: α Nitrogen (N2) / Oxygen (O2), β Water (H2O) / Sodium Chloride (NaCl). Output: ψ Nitric Acid (HNO3) ×5, ω Sodium Nitrate (NaNO3) ×5. | Medium | Multi-reactor production | 782 | 2,106GPT-6 Astra | 6/16 | — |
Precursor Compounds quantum_6 Random inputs: α Carbomega (Ω / C), β Hydrogen (H2). Output: ψ Ω-Acetylene (Ω2H2) ×10, ω Carbon Ring (C6) ×10. | Hard | Multi-reactor production | 1,050 | 5,617GPT-6 Astra | 1/16 | — |
Challenge: Going Green sensing_6 Random inputs: α Carbon Dioxide (CO2) / Hydrogen Sulfide (H2S). Output: ψ Sulfuric Acid (H2SO4) ×10, ω Carbon (C) ×10. | Medium | Multi-reactor production | 1,219 | 1,609Gemini 4 Argon | 3/16 | — |
Teleporters quantum_4 Inputs: α Tungsten Trioxide (W / O). Output: ψ Tungsten Nanospike ((W)n) ×10. | Hard | Multi-reactor production | 983 | 1,308GPT-6.1 Sol | 5/16 | — |
Challenge: In-Place Swap bonding_5 Inputs: α Nitrogen (N2), β Methane (CH4). Output: ψ Ammonia (NH3) ×10, ω Hydrogen Cyanide (HCN) ×10. | Easy | Multi-reactor production | 423 | 1,004GPT-6 Astra | 2/16 | — |
There's Something in the Fishcake production_tutorial_2 Inputs: α Hydrogen (H), β Chlorine (Cl). Output: ψ Hydrochloric Acid (HCl) ×10. | Easy | Multi-reactor production | 412 | 412GPT-6 Astra | 12/16 | — |
Falling fusion_5 Inputs: α Water (H2O), β Krypton (Kr). Output: ψ Yttrium (Y) ×5, ω Zirconium (Zr) ×5, ξ Niobium (Nb) ×5. | Medium | Multi-reactor production | 874 | 1,620Sonnet 5.5 | 4/16 | — |
Sleepless on Sernimir IV production_tutorial_3 Inputs: α Hydrogen (H), β Oxygen (O), γ Carbon (C). Output: ψ Formaldehyde (CH2O) ×10. | Easy | Multi-reactor production | 805 | 811GPT-6 Astra | 7/16 | — |
Nothing Works bonding_7 Inputs: α Methane (CH4), β Nitrogen (N2). Output: ψ Hydrogen Cyanide (HCN) ×10, ω Hydrogen (H2) ×10. | Easy | Multi-reactor production | 413 | 873GPT-6 Astra | 3/16 | — |
Σ-Ethylene organic_6 Inputs: α Hydrogen (H2), β Diatomic Sigma (Σ2). Output: ψ Σ-Ethylene (Σ2H4) ×20, ω Ethylene (C2H4) ×20. | Hard | Multi-reactor production | 2,011 | 3,689GPT-6 Astra | 3/16 | — |
Settling into the Routine bonding_6 Inputs: α Methane (CH4). Output: ψ Hydrogen (H2) ×10, ω Ethane (C2H6) ×10. | Easy | Multi-reactor production | 820 | 827GPT-6 Astra | 9/16 | — |
Molecular Foundry mining_5 Random inputs: α Iron Oxide (Fe / O) / Carbon (C). Output: ψ Cementite (Fe / C) ×10. | Medium | Multi-reactor production | 1,618 | 2,423GPT-6 Astra | 4/16 | — |
Gas Works Park mining_4 Random inputs: α Carbon (C), β Water (H2O). Output: ψ Methane (CH4) ×10, ω Carbon Dioxide (CO2) ×10. | Hard | Multi-reactor production | 820 | 1,568GPT-6.1 Sol | 6/16 | — |
Challenge: KOHCTPYKTOP mining_6 Inputs: α Silicon Dioxide (Si / O), β Arsenic (As), γ Boron (B). Output: ψ Silicon Fragment (Si) ×10, ω Silicon Fragment (+) (Si / B) ×10, ξ Silicon Fragment (-) (Si / As) ×10. | Hard | Multi-reactor production | 3,351 | 11,041GPT-6 Astra | 2/16 | — |