STEALTHMARK · HEAD TO HEAD

All comparisons ↗

Cat Jam Free vs GPT-5.6 Terra

GPT-5.6 Terra leads Cat Jam Free by 12.3 points on StealthMark, 45.8 to 33.5. It leads on 8 of 9 benchmarks, including Latch, and Cat Jam Free on 1, including Foresight. GPT-5.6 Terra scores higher on Newton's Mirror, with its largest category advantage in state at 600 ms.

See the difference ↘
Model guide ↗
All results ↗

Overall StealthMark

33.5/100Overall rank 40/53
45.8/100Overall rank 25/53

General Intelligence

27.7/100
41.9/100

Visual Intelligence

43.0/100
52.7/100

Reasoning efficiency

On every task, result quality and reasoning tokens are each compared with all measured models and weighed equally. Each dot is one model.

Single-step reasoning Result quality weighed against reasoning tokens on a single problem

Multi-step reasoning Result quality weighed against reasoning tokens across connected steps, as in agentic workflows

  • GPT-5.6 Terra

Open or local

NeitherApache-2.0

BENCHMARK BY BENCHMARK

Where each model leads

  • Cat Jam Free
  • GPT-5.6 Terra
  • Other models
  • Median

DATASHEET

Specs and pricing

  • Cat Jam Free
  • GPT-5.6 Terra
  • Other models
  • Median
PricePer 1M output tokens, input below
Cat Jam Free: No list priceGPT-5.6 Terra: $12$2 input
Context windowTokens per request, max output below
Cat Jam Free: Not publishedGPT-5.6 Terra: 1.05M128K max output
Output speedTokens per second, our measurement
Cat Jam Free: Not measuredGPT-5.6 Terra: 102tokens/s
Developer
Not publishedOpenAI
Released
Not published9 Jul 2026
Origin
Not publishedUnited States
Input → output
Not publishedText, image → text

Full datasheets, every price and sourceGPT-5.6 Terra ↗

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.

Cat Jam Free 33.8/100Rank 26/47

Survived 1 of 3
Foresight: complete playing field
Level 39 ptsTurn 20 / 20

GPT-5.6 Terra 30.1/100Rank 31/47

Survived 0 of 3
Foresight: complete playing field
Level 36 ptsTurn 7 / 20

Points per level

LevelCat Jam FreeGPT-5.6 Terra
Level 1Second Thoughts
5 ptsOut of lives
5 ptsOut of lives
Level 2Pressure Pot
6 ptsOut of lives
9 ptsOut of lives
Level 3Hide or Flight
9 ptsSurvived
6 ptsOut of lives

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.

Cat Jam Free 33.9/100Rank 33/48

Cleared 2 of 5
Latch: complete playing field
Level 56 ptsTurn 25 / 40

GPT-5.6 Terra 80.0/100Rank 9/48

Cleared 5 of 5
Latch: complete playing field
Level 520.6 ptsTurn 27 / 40

Points per level

LevelCat Jam FreeGPT-5.6 Terra
Level 1Hold the door
5.2 ptsCleared
5.2 ptsCleared
Level 2Crossfeed
9.8 ptsCleared
9.6 ptsCleared
Level 3Relay vault
10 ptsFinished early
19.2 ptsCleared
Level 4Passing bay
10.8 ptsFinished early
18.2 ptsClearedFinished early · 3 beacons left
Level 5Second thoughts
6 ptsFinished early
20.6 ptsCleared

Newton's Mirror

Same task instructions

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

The judgment

Cat Jam Free

The image conveys a supported central sphere, separate black paint and crimson below cyan. Its contact and transport story is partially resolved. The exterior cutaway camera and largely missing mirror system dominate the limitations; isolated discs and smooth highlights provide little coherent optical structure.

GPT-5.6 Terra

The real sphere and airborne black blob are substantially too low in the complete frame after accounting for aspect ratio. The first wall and floor reflections have incompatible placement, relative size or silhouette. Both lateral regions lack the references' receding lane-and-chain organization. The few recognizable mirror images provide limited optical structure. The main, side and floor spheres replace nested mirror imagery with smooth bands, while sparse planar light patches and broad spherical highlights fail to establish coherent repeated emitter mapping.

Score breakdown

CategoryCat Jam FreeGPT-5.6 Terra
State at 600 ms14.0/2524.0/25
Camera and placement4.0/156.0/15
Reflections3.5/1207.0/120
Materials and scale4.0/105.5/10
Floor-damage reward0.0/100.0/10

Benchmark task

A spinning metal sphere and paint in a mirrored room test physical reasoning, perspective and consistency across repeated reflections.

Selfie

Different task instructions

Visual construction and creative interpretation.

The judgment

Cat Jam Free

A coherent, restrained cat illustration captures the pale palette and intent eyes. Its central expressive requirement—the committed forward-and-down neck bob—is insufficiently articulated. Simple geometry, faint paw construction and minimal surface detail limit the physical presence and finish.

GPT-5.6 Terra

Six ivory heads and rounded lobes create a striking radial emblem around a clear hexagonal opening. Soft shading gives the bodies volume, but abrupt rectangular and diagonal band endings make the continuous alternating weave ambiguous. Repetitive scale lines and simplified faces convey an ornamental serpent more convincingly than living anatomy.

Score breakdown

CategoryCat Jam FreeGPT-5.6 Terra
Task & likeness5.5/107.5/10
Anatomy & construction5.5/105.5/10
Space & placement6.0/107.0/10
Light & reflections6.0/107.5/10
Purposeful detail4.0/106.5/10
Artistry & character5.5/105.5/10
Materials & effects5.0/106.5/10
Visual integrity6.5/105.0/10

Benchmark task

Cat Jam Free

An ivory cat nods intently to music beside a tiny speaker. The scene tests feline anatomy, movement conveyed through a still pose and the contrast between pale fur and woven fabric.

GPT-5.6 Terra

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.

Mona Lisa

Different task instructions

Precise visual recall and portrait reconstruction.

The judgment

Cat Jam Free

The portrait is recognizable and cleanly assembled, but replication remains basic. Its frontal symmetry, elongated silhouette, simplified facial likeness and unresolved hands differ markedly from the original. Modest skin gradients provide volume, while clothing and landscape rely on broad, flat shapes.

GPT-5.6 Terra

The dark clothing, central portrait and restrained smile evoke the Mona Lisa, but replication is limited by the broad face, elongated neck, nearly frontal pose and indistinct landscape. Soft gradients give the face some volume. Crossed arms become rounded masses without readable fingers or wrists, and the expression lacks the original's subtlety. Clean framing and curves support an otherwise basic, uneven portrait.

Score breakdown

CategoryCat Jam FreeGPT-5.6 Terra
Task & likeness2.5/104.0/10
Anatomy & construction2.0/103.0/10
Space & placement4.0/104.5/10
Light & reflections3.5/105.0/10
Purposeful detail3.0/104.0/10
Artistry & character3.0/104.0/10
Materials & effects2.5/104.0/10
Visual integrity5.5/106.0/10

Benchmark task

An SVG interpretation of the Mona Lisa tests facial likeness, anatomy and the composition of a familiar portrait.

Beach

Same task instructions

Creativity, perspective and visual beauty.

The judgment

Cat Jam Free

The scene clearly supplies the requested beach subjects and playful activity. Clean silhouettes and warm gradients support readability, but elementary drawing, ambiguous parasol construction, weak grounding and a rigid sun reflection limit its depth and finish.

GPT-5.6 Terra

Warm sunset gradients, framing palms and colorful beach activities create an appealing scene. Animals, birds and a sun reflection fulfill the brief. The dog and turtle remain schematic, foreground depth is shallow, and the reflection forms rigid bands. Clean silhouettes and readable accessories support a competent illustration, but limited anatomy, material variation and lighting keep it below exceptional.

Score breakdown

CategoryCat Jam FreeGPT-5.6 Terra
Task & likeness7.0/107.5/10
Anatomy & construction4.5/105.0/10
Space & placement4.5/106.0/10
Light & reflections4.0/105.0/10
Purposeful detail4.0/106.5/10
Artistry & character4.5/105.0/10
Materials & effects4.5/105.5/10
Visual integrity5.5/105.0/10

Benchmark task

A busy shoreline at sunset tests scene composition, animal forms and the relationship between light and water reflections.

Ground Truth

Same task instructions

Physical reasoning, light and visual reconstruction.

The judgment

Cat Jam Free

This benchmark has not been assessed yet.

GPT-5.6 Terra

This benchmark has not been assessed yet.

Benchmark task

A plank, computer mouse and blueberry in a steel room test physical stability, spatial relationships, materials and lighting.

Raccoon

Same task instructions

Scene composition and interacting subjects.

The judgment

Cat Jam Free

An appealing cartoon demonstrates the back-riding arrangement through expressive faces and clean shapes. Uncertain steering contact, indistinct deck support and weak hull-water interaction limit physical coherence. Smooth gradients add volume, but simple rounded construction and sparse material detail constrain complexity and finish.

GPT-5.6 Terra

Expressive faces, a recognizable raccoon perched on the dog, and a sweeping wake make an appealing cartoon. The principal weakness is the steering interaction: the dog's paw sits beside the control assembly without a convincing handlebar grip. Bold outlines and coherent layering provide polish, while simplified shading, compressed seating geometry and angular splashes limit depth and physical credibility.

Score breakdown

CategoryCat Jam FreeGPT-5.6 Terra
Task & likeness6.0/107.5/10
Anatomy & construction5.0/105.0/10
Space & placement5.0/107.0/10
Light & reflections5.0/106.0/10
Purposeful detail6.0/107.0/10
Artistry & character5.0/105.0/10
Materials & effects5.0/107.0/10
Visual integrity4.5/107.5/10

Benchmark task

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.

Pelican

Same task instructions

Subject construction and spatial relationships.

The judgment

Cat Jam Free

A coherent cartoon with readable bicycle placement, controlled outlines and modest surface shading. The separated-looking upper bill weakens pelican likeness; schematic limbs, uncertain gripping contact and simplified mechanics constrain construction. Opaque wheel interiors flatten spatial relationships. Limited feather complexity and directional lighting keep the finish modest.

GPT-5.6 Terra

The oversized bill, expressive eye and balanced twilight palette make the cyclist immediately readable. Clean contours and wheel details support the illustration, but the rabbit-like head tufts weaken pelican likeness. The wing does not clearly grip the handlebar, pedal contact is uneven, and the drivetrain is incomplete. Lighting remains mostly decorative.

Score breakdown

CategoryCat Jam FreeGPT-5.6 Terra
Task & likeness7.0/106.0/10
Anatomy & construction5.0/106.0/10
Space & placement6.0/107.0/10
Light & reflections5.0/106.5/10
Purposeful detail5.5/107.0/10
Artistry & character5.5/106.5/10
Materials & effects6.5/106.5/10
Visual integrity6.5/107.0/10

Benchmark task

A cycling pelican tests anatomy, riding posture and contact between the bird and the bicycle.