How to make a skybox or game level with AI

Short answer: AI tools like Blockade Labs Skybox AI and World Labs Marble can turn a text prompt into a 360 degree sky or a whole explorable world, and you can try both for free. But neither free plan lets you download the result, so for a sky you can actually ship today, grab a free CC0 HDRI from Poly Haven, and build the level itself from a free CC0 kit by Kenney or Quaternius. Every plan limit and license below comes from each company's own site, checked Oct 24, 2026. We only cover free plans, plus the first paid step where it matters.

The 30 second version

• Free sky you can ship: a Poly Haven HDRI. CC0, commercial use, no credit needed.
• AI sky from a prompt: Skybox AI. Free plan is view only with 5 generations. Downloads start on Essential at $24/mo ($20/mo billed yearly).
• AI world you can walk around: World Labs Marble. Free plan generates up to 4 worlds, but exporting needs Standard ($20/mo) and commercial rights need Pro ($35/mo).
• AI props and buildings to dress a level: Sloyd. Free Guest plan, 1 text to 3D and 1 image to 3D a day, personal use only.
• The level itself: a free CC0 kit from Kenney or Quaternius, laid out in your engine or in free Blender.

Skybox and level tools compared

Free plans first, from each tool's official pricing page, docs or store page, checked Oct 24, 2026.

Skybox or level: what do you actually need?

A skybox is the picture wrapped all the way around your scene: sky, clouds, far mountains, a space nebula. The player can never reach it. Usually it is one 360 degree image in a 2:1 shape (called equirectangular or a panorama), and an HDR version also lights your scene. A level is the part the player touches: floors, walls, stairs, trees, crates, with collision so they do not fall through.

AI is already good at skyboxes, because a sky is just a picture. It is still weak at levels, because a good level is about layout, paths and fun, not just looks. So the beginner plan is: get a sky from AI or a free HDRI, then build the level from a kit and tune it by hand.

Option A: Skybox AI by Blockade Labs (AI skies from a prompt)

Type a scene, like "floating islands at sunset, painted fantasy style", pick a style, and Skybox AI generates a full 360 degree sky. Blockade Labs' plans page (checked Oct 24, 2026) shows:

• Free: create and remix skyboxes, view only. 5 generations, a watermark, and no downloads or exports.
• Essential: $24/mo, or $20/mo billed yearly. 100 credits a month and 4K exports. Blockade calls it best for solo creators working on personal projects.
• Standard: $60/mo per seat, or $48/mo billed yearly. 300 credits, 8K exports, its latest model, batch generation and API key access.
• Business: $140/mo, or $112/mo billed yearly. 500 credits, 16K exports, HDRI exports, IP protection and Commercial licensing.

Unverified: the plan cards list "Commercial licensing" only on Business. Whether Essential or Standard lets you sell a game with your skyboxes is not spelled out on the plans page, so ask Blockade before you ship. How many credits one skybox costs in the web app is also not listed there, so check in the app.

Good for: trying ideas for your game's mood in minutes for free, then paying for one month when you know what you want.

Option B: World Labs Marble (AI worlds you can walk through)

Marble turns a text prompt, an image or a 360 panorama into a 3D world you can explore in the browser. World Labs' billing docs (checked Oct 24, 2026) list four plans:

• Free: generate worlds from a text prompt, a single image or a 360 panorama. Up to 4 world generations. World Labs' export docs say the Free plan can generate worlds but not export them.
• Standard ($20/mo): up to 12 world generations, editing, generation from multiple images, videos or 3D layouts, and exports: Gaussian splats (SPZ and PLY), 360 panoramas and collider meshes.
• Pro ($35/mo): up to 25 world generations, high quality textured mesh (GLB) export and commercial rights to generated worlds.
• Max: up to 75 world generations. The price was not shown on the docs page we checked, so it is unverified here.

The $20 and $35 prices come from the upgrade example in World Labs' billing docs. Its pricing page at marble.worldlabs.ai showed a waitlist page when we checked, so we could not confirm prices there. Credits are spent per action: a basic world from a single image uses 1,580 credits, per the docs.

What you get when you export

Per World Labs' export file specs: a 360 panorama PNG at 2560 x 1280 pixels, splat files of about 2 million or about 500,000 splats, a coarse collider mesh GLB for simple physics, and on Pro a high quality mesh GLB (around 600k triangles with textures, or around 1M with vertex colors) that can take up to an hour to generate.

• three.js: World Labs recommends Spark, a three.js library for splats, and says its own website is built on it.
• Unity: World Labs' Unity page points to the free aras-p UnityGaussianSplatting plugin, says it works well on Unity 6.1, and recommends a patched fork for Marble files.
• Unreal: World Labs lists several Windows plugins. For example, VIVE Mars Nova 3DGS is an invite-only private beta for Unreal Engine 5.4 to 5.6, and Volinga is paid with a watermarked, non-commercial 14 day trial.
• Godot: not listed in World Labs' export docs. The simplest route is to use the exported 360 panorama as a sky.

Splats look great but are not normal game geometry. For a playable level you still need collision (the collider mesh helps) and your own gameplay on top.

Option C: Sloyd (AI props and buildings to dress a level)

Sloyd makes 3D props and buildings from templates you adjust with sliders, plus text to 3D and image to 3D. Sloyd's pricing page (checked Oct 24, 2026) shows a free Guest plan with 1 text to 3D and 1 image to 3D generation a day, the scene and template editors, image exports, and model exports for community models only. Guest has a personal-use license. The AI skybox, commercial use and plugins for Unity, Unreal and Blender start on Plus at $15/mo ($12.50/mo billed yearly). Sloyd says its exports, such as GLB, OBJ and FBX, work with Unity, Unreal, Godot, Roblox Studio and Blender.

Dungeon Alchemist: not AI, and not for engine levels

Dungeon Alchemist often shows up in "AI level generator" lists, so here are the facts. Its Steam page (checked Oct 24, 2026) says it is mapmaking software for tabletop RPGs, that it does not use any generative AI or LLMs for room generation, and that its procedural algorithms only use content from its own paid artists. It costs $44.99 on Steam with no free plan, and it is in Early Access. Its FAQ lists printable images and imports into virtual tabletops (Foundry, Roll20 and Fantasy Grounds) as the outputs. We found no official export to Godot, Unity or Unreal. Its terms of use allow limited commercial use, but a company with more than $100,000 in annual turnover needs a custom professional license. Great for planning a top down dungeon layout on paper, not for building the level itself.

The free, non-AI way (and often the best way)

• Sky: Poly Haven HDRIs. Poly Haven's license page (checked Oct 24, 2026) says all its HDRIs, textures and models are CC0: any purpose including commercial work, no credit required, and you can include them in a product you sell. HDRIs download as .hdr or .exr at several resolutions starting at 1K. Godot's own docs point to Poly Haven for freely licensed HDRIs.
• Level pieces: Kenney. Kenney's support page (checked Oct 24, 2026) says all game assets on its asset pages are public domain (CC0), free for commercial projects, and attribution is not required.
• Low poly worlds: Quaternius. Quaternius' FAQ (checked Oct 24, 2026) says its models are CC0 and free to use without attribution in commercial, educational and personal projects. Formats vary by pack, so check each pack page.
• Textures for floors and walls: ambientCG (CC0) and Poly Haven.
• Layout: Blender. Free and open source under the GNU GPL, and Blender's license page says you are free to sell your work. You can also lay out kit pieces directly in your engine's editor, which is often easier for a first level.

More free libraries are in free game assets for beginners.

How to import a skybox (HDRI or 360 image)

Godot

From Godot's Environment docs (4.7, checked Oct 24, 2026):

1. Add a WorldEnvironment node to your scene and create a new Environment on it.
2. Set Background, Mode to Sky, then create a Sky with a PanoramaSkyMaterial.
3. Drop your 360 image into the panorama slot. Godot recommends a 2:1 image, and it must be .hdr or .exr to get high dynamic range (a .png or .jpg works, but without HDR lighting).
4. By default the sky also lights your scene and shows up in reflections. If a photo HDRI with a visible sun causes sparkles, select the texture, turn on HDR Clamp Exposure in the Import dock and click Reimport.

Unity

From Unity's Create a skybox and Panoramic skybox pages (checked Oct 24, 2026):

1. Drop the .hdr, .exr, .png or .jpg file into your Assets folder. Unity reads EXR and HDR files.
2. Choose Assets, Create, Material. In the Shader dropdown, search "skybox" and pick Skybox/Panoramic.
3. Put your image in the Spherical (HDR) slot, set Mapping to Latitude Longitude Layout and Image Type to 360.
4. Open Window, Rendering, Lighting, go to the Environment tab and drag the material into Skybox Material.

Unity's docs say the Panoramic skybox works in the Built-in Render Pipeline and URP, but not HDRP. If your sky has a visible sun, rotate a Directional Light to match it.

Unreal Engine

From Epic's HDRI Backdrop docs (UE 5.8 docs, checked Oct 24, 2026):

1. Edit, Plugins, find HDRI Backdrop under Rendering, enable it and click Restart Now.
2. Import your latitude longitude HDR image into the Content Browser. In the texture editor, set Mip Gen Settings to NoMipmaps and set Maximum Texture Size to match the image's larger side, or it will look low resolution.
3. In Place Actors, under Lights, drag HDRI Backdrop into the level and set its Cubemap to your HDR image.

The HDRI Backdrop handles the background mesh, ground projection with shadow catching, and ambient light from its Sky Light, which makes it quick for a first scene.

three.js

three.js' HDRLoader docs show loading a .hdr file as an equirectangular environment map, and the Scene docs say scene.background accepts equirectangular textures as a skybox. Adapted from those docs (checked Oct 24, 2026):

import * as THREE from 'three';
import { HDRLoader } from 'three/addons/loaders/HDRLoader.js';

const envMap = await new HDRLoader().loadAsync('/sky/my_sky_2k.hdr');
envMap.mapping = THREE.EquirectangularReflectionMapping;
scene.background = envMap;   // the sky you see
scene.environment = envMap;  // lighting and reflections for physical materials

three.js deprecated the old name, RGBELoader, in r180 in favor of HDRLoader. Use a 1K or 2K HDRI for the web so the page loads fast.

How to import a level or props

• Godot: use GLB (glTF 2.0), the format Godot's docs recommend. Copy it into your project and Godot imports it.
• Unity: FBX is Unity's recommended import format. For GLB files, install Unity's glTFast package.
• Unreal Engine: import FBX through the Content Browser.
• three.js: load GLB files with GLTFLoader. See How to make a browser game with three.js and AI.

Whatever the source, add simple collision (boxes and planes are fine) to floors and walls, and keep the parts the player touches hand placed, even if the scenery came from AI.

Before you ship: commercial use checklist

1. Skybox AI Free: no exports and no commercial licensing. Commercial licensing is listed on Business. Essential and Standard are unverified for selling a game, so ask Blockade.
2. World Labs Marble Free and Standard: commercial rights to generated worlds start on Pro.
3. Sloyd Guest: personal-use license only. Commercial use starts on Plus.
4. Dungeon Alchemist: limited commercial use, but companies over $100,000 in annual turnover need a professional license.
5. Poly Haven, Kenney, Quaternius: CC0, so you are free to ship.
6. Steam: if any shipped art is AI generated, disclose it. More in Can I sell a game made with AI art?

Not legal advice. Plans and terms change often, so re-check each official page before you pay or ship.

Sources, checked Oct 24, 2026: Skybox AI plans, World Labs subscriptions and billing, Exporting from Marble, Marble export file specs, Sloyd pricing, Dungeon Alchemist on Steam, Dungeon Alchemist terms, Poly Haven license, Kenney support, Quaternius FAQ, Blender license, Godot Environment docs, Unity skybox docs, Unreal HDRI Backdrop docs, three.js HDRLoader docs.

Related

Need props and characters for your level? Read Best free AI 3D model generators for game assets and How to animate a 3D character for free. New to all of this? Start with Make your first game with free AI tools. Browse every level and world generation tool, 3D model and texture tool and free asset library on StarterLoot.

FAQ

Can I make a skybox with AI for free?

You can try it, but the free plans we checked do not let you download one. Blockade Labs' Skybox AI Free plan (checked Oct 24, 2026) is view only, with 5 generations, a watermark and no exports. World Labs Marble's Free plan generates up to 4 worlds but cannot export them. Sloyd's AI skybox is only on its paid Plus plan. For a free sky you can ship today, download a CC0 HDRI from Poly Haven.

Can I use a Skybox AI skybox in a commercial game?

Check with Blockade Labs first. Its plans page (checked Oct 24, 2026) lists Commercial licensing only on the Business plan ($140 a month, or $112 a month billed yearly). Essential is described as best for personal projects. Whether Essential or Standard covers selling a game is unverified, so ask Blockade before you ship.

What is the best free skybox for a beginner?

A Poly Haven HDRI. Poly Haven's license page (checked Oct 24, 2026) says every asset is CC0: any use including commercial, no credit required. Its HDRIs download as .hdr or .exr files, which Godot, Unity, Unreal and three.js can all use as a sky and as lighting.

Can AI make a whole playable game level?

Not really, yet. World Labs Marble generates explorable 3D worlds, but on the plans that export them you get Gaussian splats, a 360 panorama and a coarse collider mesh, and the high quality textured mesh needs the Pro plan. You still place gameplay, enemies and paths yourself. For a first game, a free CC0 kit from Kenney or Quaternius plus your engine's editor is the faster way to a level that plays well.

How do I put a skybox into Godot?

Add a WorldEnvironment node, give it an Environment, set Background to Sky, and pick a PanoramaSkyMaterial with your 360 image. Godot's docs (4.7, checked Oct 24, 2026) recommend a 2:1 image, and say it must be .hdr or .exr to get high dynamic range.

Is Dungeon Alchemist an AI tool?

No. Its Steam page (checked Oct 24, 2026) says it does not use any generative AI or LLMs for room generation, and uses in-house procedural algorithms with content from its own paid artists. It is made for tabletop RPG maps, costs $44.99 on Steam with no free plan, and its FAQ lists printable images and virtual tabletop exports, not game engine levels.