STEALTHMARK · HEAD TO HEAD

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GPT 5.6 Terra vs Union Alpha

Union Alpha scores 8.9 points higher overall (60.0 vs 51.1). Union Alpha scores higher on Newton's Mirror, with its largest category advantage in reflections. Union Alpha’s overall score includes one estimated scene.

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Overall StealthMark

51.1/100
60.0/100Estimated · 1 missing scene

General Intelligence

31.1/100
40.9/100Partial coverage

Visual Intelligence

66.2/100
73.2/100Partial coverage

Newton's Mirror

Same prompt

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

GPT 5.6 Terra23.3/100

GPT 5.6 Terra: Newton's Mirror SVG benchmark
Researcher observations

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.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

Union Alpha38.3/100

Union Alpha: Newton's Mirror SVG benchmark
Researcher observations

Recognizable near-field sphere placement and bilateral convergence provide limited optical structure. Broad gray regions interrupt lateral sightlines and truncate side-floor images. Missing outer chains, absent nested sphere imagery and incomplete planar and curved emitter mappings dominate the reflection system.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

Compare category scores
CategoryGPT 5.6 TerraUnion Alpha
State at 600 ms23.5/2525.0/25
Camera and placement6.0/1515.0/15
Reflections7.0/12019.0/120
Materials and scale5.5/1010.0/10
Floor-damage reward0.0/100.0/10

Selfie

GPT 5.6 Terra73.0/100

GPT 5.6 Terra: Selfie SVG benchmark
Researcher observations

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.

Prompt withheld

This prompt is held back to prevent benchmaxxing.

Compare category scores
CategoryGPT 5.6 TerraUnion Alpha
Prompt & likeness7.5/10—
Anatomy & construction6.5/10—
Space & placement7.5/10—
Light & reflections7.5/10—
Purposeful detail7.0/10—
Artistry & character8.0/10—
Materials & effects7.0/10—
Visual integrity7.5/10—

Beach

Different prompts

GPT 5.6 Terra73.3/100

GPT 5.6 Terra: Beach SVG benchmark
Researcher observations

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.

Exact prompt

Create an SVG of a amazing beach scene. Sunset, animals, fun, birds, reflections Make it a masterpiece, no tools allowed

Union Alpha80.0/100

A beach at sunset with a palm tree, turtle, crab, birds, and a leaping dolphin.
Researcher observations

A cohesive sunset palette, sweeping shoreline and playful animals make an appealing beach illustration. The sun’s reflection establishes a clear focal axis, balanced by the palm and umbrella. Clean silhouettes and small decorative features reward inspection, though simplified anatomy, repetitive reflection bars and generic oval shadows limit volume and naturalism.

Exact prompt

Create an SVG of a amazing beach scene. Sunset, animals, fun, birds, reflections

Compare category scores
CategoryGPT 5.6 TerraUnion Alpha
Prompt & likeness8.5/109.0/10
Anatomy & construction7.0/107.5/10
Space & placement7.0/108.0/10
Light & reflections6.5/107.5/10
Purposeful detail7.0/108.0/10
Artistry & character7.5/108.0/10
Materials & effects6.5/107.0/10
Visual integrity8.0/108.5/10

Mona Lisa

Different prompts

GPT 5.6 Terra49.5/100

GPT 5.6 Terra: Mona Lisa SVG benchmark
Researcher observations

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.

Exact prompt

Replicate mona-lisa as SVG Make it a masterpiece, no tools allowed

Union Alpha64.0/100

An SVG interpretation of the Mona Lisa, with folded hands and a landscape background.
Researcher observations

The centered portrait, folded hands, dark clothing and hazy landscape clearly evoke the Mona Lisa. Muted colors and soft facial shading create a coherent illustration, but replication remains schematic: the face is broad, eyes outlined, smile simplified and overlapping fingers poorly resolved. Angular landscape shapes and flat fabric limit depth and painterly richness.

Exact prompt

Replicate mona-lisa as SVG

Compare category scores
CategoryGPT 5.6 TerraUnion Alpha
Prompt & likeness5.0/107.0/10
Anatomy & construction4.0/106.0/10
Space & placement5.5/106.5/10
Light & reflections6.0/106.5/10
Purposeful detail3.5/105.5/10
Artistry & character5.0/106.5/10
Materials & effects4.5/105.0/10
Visual integrity6.5/107.5/10

Raccoon

Different prompts

GPT 5.6 Terra72.0/100

GPT 5.6 Terra: Raccoon SVG benchmark
Researcher observations

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.

Exact prompt

Generate an SVG: A raccoon sits on a dog's back while the dog steers a jet ski Make it a masterpiece, no tools allowed

Union Alpha72.0/100

A raccoon rides on a dog as the dog steers a red jet ski.
Researcher observations

Expressive animals, a readable riding arrangement and sweeping spray create an appealing cartoon. The raccoon sits convincingly on the dog's back, but the dog's paw does not clearly grip the handlebar, whose connection to the hull is unresolved. Flat lighting provides little volume or reflection. A dark rectangular strip interrupts the upper-right background.

Exact prompt

A raccoon sits on a dog's back while the dog steers a jet ski

Compare category scores
CategoryGPT 5.6 TerraUnion Alpha
Prompt & likeness7.5/108.0/10
Anatomy & construction6.0/106.5/10
Space & placement7.5/107.5/10
Light & reflections6.5/105.5/10
Purposeful detail7.5/107.5/10
Artistry & character8.0/108.0/10
Materials & effects7.0/107.5/10
Visual integrity8.0/107.0/10

Pelican

Benchmax control

Outside General and Visual Intelligence.

GPT 5.6 Terra70.5/100

GPT 5.6 Terra: Pelican SVG benchmark
Researcher observations

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.

Exact prompt

Generate an SVG of a pelican riding a bicycle Make it a masterpiece, no tools allowed

Union Alpha73.8/100

A pelican riding a teal bicycle beneath a sunny blue sky.
Researcher observations

The pelican is immediately recognizable, with an expressive face, convincing bill silhouette and appealing pastel composition. Both legs connect to feet, and the wing reaches the handlebar. Bicycle construction is less resolved: the far pedal lacks a clear crank connection and no chain is visible. Clean contours and orderly spokes support the illustration, while flat lighting and simplified surfaces limit depth.

Exact prompt

Generate an SVG of a pelican riding a bicycle

Compare category scores
CategoryGPT 5.6 TerraUnion Alpha
Prompt & likeness8.0/108.5/10
Anatomy & construction6.0/106.5/10
Space & placement7.0/107.5/10
Light & reflections6.5/106.0/10
Purposeful detail7.0/107.0/10
Artistry & character7.5/108.0/10
Materials & effects6.5/106.5/10
Visual integrity8.0/108.5/10