GPT-5.6 Sol 62.9/100Rank 8/47

STEALTHMARK · HEAD TO HEAD
All comparisons ↗GPT-5.6 Sol leads Muse Spark Open by 10.0 points on StealthMark, 54.1 to 44.1. It leads on 8 of 9 benchmarks, including both games, and Muse Spark Open on 1. GPT-5.6 Sol scores higher on Newton's Mirror, with its largest category advantage in state at 600 ms.
See the difference ↘On every task, result quality and reasoning tokens are each compared with all measured models and weighed equally. Each dot is one model.
BENCHMARK BY BENCHMARK
DATASHEET
GPT-5.6 Sol scores higher on StealthMark. Muse Spark Open is 4.7× cheaper per output token and runs 4.4× faster in our speed test. Both take about 1.05M tokens of context.
Full datasheets, every price and sourceGPT-5.6 Sol ↗Muse Spark Open ↗
Anticipating threats and planning ahead. Collect coins while avoiding ghosts. Ghosts move before the player each turn, and collisions cost a life. 3 levels in sequence, up to 66 turns in total. Earlier moves and outcomes carry forward, testing learning across levels.


Cooperative planning and learning from experience. Coordinate two robots to push numbered cores onto matching sockets. Pressure plates hold doors open; moving either robot uses one turn. 5 levels in sequence, up to 152 turns in total. Earlier moves and outcomes carry forward, testing learning across levels.


Physics, perspective and recursive reflections, tested together. Explore the test ↗


GPT-5.6 Sol
The central sphere and paint ordering are supported, but a frontal, centrally converging chamber replaces the required corner perspective. The first wall and floor images have incorrect placement and scale relationships. Sparse reflection cues remain, while continuous outer chains, open lateral sightlines, dense planar light sequences and curved nested spherical imagery are largely missing.
Muse Spark Open
The airborne black blob and deformed paint support the broad contact sequence, although cyan attachment and wheel-directed transport remain partial. The sphere and black blob have substantial framing errors. The dominant limitation is the largely absent mirror system: faint wall circles and isolated highlights provide little evidence of recursive room geometry or curved nested reflections. Oversized compact paint features and diffuse material treatment further limit credit.
| Category | GPT-5.6 Sol | Muse Spark Open |
|---|---|---|
| State at 600 ms | 23.0/25 | 14.0/25 |
| Camera and placement | 6.0/15 | 6.0/15 |
| Reflections | 11.0/120 | 8.0/120 |
| Materials and scale | 7.5/10 | 3.5/10 |
| Floor-damage reward | 0.0/10 | 0.0/10 |
A spinning metal sphere and paint in a mirrored room test physical reasoning, perspective and consistency across repeated reflections.
Visual construction and creative interpretation.


GPT-5.6 Sol
Six evenly spaced lobes, outward-facing heads and a clear central hexagon establish the requested knot. The ivory silhouette is controlled, but broad crossing bands resemble rigid strips, shading provides limited muscular volume, and repetitive scale lines extend across black loop openings. Small oval heads have readable eyes and mouths but limited anatomical character or moist surface detail.
Muse Spark Open
The rounded silhouette and asymmetric expression make an appealing baby elephant, supported by a quiet background and grounding shadow. The protective action remains difficult to read: forefeet cannot be confidently traced into a grip, and seed contact is crowded by fine lines. Controlled simple shapes provide charm, but limited anatomical clarity, shading and surface detail leave the execution uneven.
| Category | GPT-5.6 Sol | Muse Spark Open |
|---|---|---|
| Task & likeness | 7.5/10 | 5.0/10 |
| Anatomy & construction | 6.0/10 | 4.5/10 |
| Space & placement | 7.0/10 | 6.0/10 |
| Light & reflections | 5.0/10 | 5.0/10 |
| Purposeful detail | 6.0/10 | 6.0/10 |
| Artistry & character | 6.5/10 | 5.0/10 |
| Materials & effects | 4.5/10 | 5.0/10 |
| Visual integrity | 6.0/10 | 6.5/10 |
GPT-5.6 Sol
A pale serpent woven into an interlocking knot tests connected anatomy, repeated structure and readable overlaps. Organic surface detail must work with the overall geometry.
Muse Spark Open
A small elephant protecting a delicate seed tests expressive anatomy, physical contact and contrasting organic materials.
Precise visual recall and portrait reconstruction.


GPT-5.6 Sol
The crossed hands, dark dress and winding landscape establish the Mona Lisa composition. Replication is limited by enlarged eyes, an elongated face and a more frontal pose. Broad gradients suggest volume, but outlined features and flattened, overlapping fingers weaken the portrait. The frame and restrained palette unify the image; visible grain adds texture without convincing painterly transitions.
Muse Spark Open
A recognizable, orderly interpretation with clean major contours, connected body forms and modest facial shading. Wide eyes, frontal symmetry and schematic hands limit likeness and expression. Layered scenery establishes basic depth, but shallow arm overlaps, flat clothing and sparse fine detail keep the execution basic and uneven.
| Category | GPT-5.6 Sol | Muse Spark Open |
|---|---|---|
| Task & likeness | 4.5/10 | 3.0/10 |
| Anatomy & construction | 4.0/10 | 3.0/10 |
| Space & placement | 5.5/10 | 5.0/10 |
| Light & reflections | 5.0/10 | 4.5/10 |
| Purposeful detail | 5.0/10 | 4.0/10 |
| Artistry & character | 4.5/10 | 3.0/10 |
| Materials & effects | 5.5/10 | 4.0/10 |
| Visual integrity | 6.5/10 | 6.0/10 |
An SVG interpretation of the Mona Lisa tests facial likeness, anatomy and the composition of a familiar portrait.
Creativity, perspective and visual beauty.


GPT-5.6 Sol
The purple-to-gold sunset, framing palms and varied beach activities create an appealing, coherent illustration. The sun’s reflection establishes a clear focal path. Figures and animals are recognizable but geometrically simplified; airborne dolphins lack convincing splashes, and the boat reflection is schematic. Clean silhouettes and playful details succeed more strongly than anatomical depth or material realism.
Muse Spark Open
A coherent sunset beach with readable activities, balanced framing and controlled colour transitions. Small accessories add interest, but schematic anatomy, limited surface detail, weak directional shadows and a geometric reflection constrain its finish. Most shapes and overlaps remain clean.
| Category | GPT-5.6 Sol | Muse Spark Open |
|---|---|---|
| Task & likeness | 8.5/10 | 8.0/10 |
| Anatomy & construction | 6.0/10 | 6.0/10 |
| Space & placement | 7.0/10 | 6.5/10 |
| Light & reflections | 6.5/10 | 5.5/10 |
| Purposeful detail | 7.0/10 | 6.5/10 |
| Artistry & character | 6.5/10 | 5.5/10 |
| Materials & effects | 6.5/10 | 6.0/10 |
| Visual integrity | 7.0/10 | 8.0/10 |
A busy shoreline at sunset tests scene composition, animal forms and the relationship between light and water reflections.
Physical reasoning, light and visual reconstruction.


GPT-5.6 Sol
This benchmark has not been assessed yet.
Muse Spark Open
This benchmark has not been assessed yet.
A plank, computer mouse and blueberry in a steel room test physical stability, spatial relationships, materials and lighting.
Scene composition and interacting subjects.


GPT-5.6 Sol
Expressive faces, bold silhouettes and layered waves make an appealing cartoon. The raccoon sits convincingly behind the dog's shoulders, and the dog's forward paw reaches the steering grip. Steering construction and seated support remain somewhat ambiguous. The glowing sunset lacks a corresponding warm reflection or consistent illumination on the riders.
Muse Spark Open
Expressive faces, distinct accessories and clean color separation make the scene appealing and recognizable. Character detail is stronger than the functional construction: steering contact, limb overlaps and seating remain ambiguous. The readable hull and lively spray establish motion, while limited directional shading and simplified surfaces constrain depth and physical coherence.
| Category | GPT-5.6 Sol | Muse Spark Open |
|---|---|---|
| Task & likeness | 6.5/10 | 4.0/10 |
| Anatomy & construction | 5.0/10 | 3.0/10 |
| Space & placement | 6.5/10 | 6.0/10 |
| Light & reflections | 6.5/10 | 4.5/10 |
| Purposeful detail | 7.5/10 | 7.0/10 |
| Artistry & character | 5.0/10 | 3.5/10 |
| Materials & effects | 7.0/10 | 5.0/10 |
| Visual integrity | 5.0/10 | 5.0/10 |
A jet-ski scene pairs a canine driver with a raccoon passenger. It tests the placement and contact of interacting subjects, along with vehicle construction.
Subject construction and spatial relationships.


GPT-5.6 Sol
The expressive pelican and balanced coastal composition remain appealing, but a sky-colored slit between the neck contours above the wing leaves the central anatomy incoherent. This visible construction and layering defect prevents a clean-integrity assessment. Clustered feet lack clear pedal contacts and the chain routing is schematic; lighting and water reflections remain graphic.
Muse Spark Open
A controlled, appealing cartoon with a recognizable pelican, expressive face and clean curved forms. Feather lines, spokes and bill shading provide useful complexity. Aligned wheels and a ground shadow establish placement, but uncertain pedal contacts and obscured mechanical connections weaken support and riding action. Lighting remains loosely coordinated with the sun.
| Category | GPT-5.6 Sol | Muse Spark Open |
|---|---|---|
| Task & likeness | 8.5/10 | 7.5/10 |
| Anatomy & construction | 5.0/10 | 5.0/10 |
| Space & placement | 7.5/10 | 6.0/10 |
| Light & reflections | 7.5/10 | 5.0/10 |
| Purposeful detail | 8.0/10 | 6.5/10 |
| Artistry & character | 6.5/10 | 5.5/10 |
| Materials & effects | 7.0/10 | 6.0/10 |
| Visual integrity | 4.5/10 | 7.5/10 |
A cycling pelican tests anatomy, riding posture and contact between the bird and the bicycle.