Build worlds. Play dreams.
REM Nebula is a world-building game for Windows. Create your own 3D, 2.5D and 2D worlds and games, make new objects just by describing them, and turn your worlds into games. Soon you'll be able to share them and step into the worlds other people dream up.
Free to download and play. Optional credits for extra AI creations.
Everything you need to build a dream
REM is the stage of sleep where dreams happen. In REM Nebula, every player's world is a dream - and you can walk into anyone's.
3D, 2.5D or 2D
Pick a dimension and a view - free-roaming 3D, bird's-eye or side-scrolling 2.5D, or 2D - and start placing things. Build in mid-air, snap, move, rotate, undo.
Turn it into a game
Add collectibles, hazards, checkpoints and a finish line, set the rules, and you've made a game. Start from a template, or learn the ropes in the Emerald Sanctuary.
Retro or modern 2D
2D worlds come in 8-bit, 16-bit, 32-bit or modern styles, with the same building tools and game pieces as 3D.
Your avatar, everywhere
Design your character in the character creator and play as them in any world - yours or someone else's.
A whole asset library
Models, building blocks, particles and effects, NPCs and enemies, music and sound effects - including an original sound pack and free-licensed sounds credited automatically.
Share and play (coming soon)
Publish your worlds, play other creators' worlds, leave likes, visit creator profiles and remix with credit. Shared worlds are checked for other people's characters and brands. Online sharing isn't open in the test build yet.
Describe it. See it. Build with it.
Need something the library doesn't have? Describe it, and REM Nebula makes it for you - first as a picture, then as a 3D model you can place in your world.
Describe an object
"A small wooden treasure chest with brass corners." Descriptions are checked first: no characters or brands owned by someone else, nothing unsafe.
Get a picture
A picture of your object appears in a few seconds. Try again until it's right - or use a picture of your own instead.
Turn it into a 3D model
In about a minute the picture becomes a textured 3D model, ready to place, scale and use in your game.
Made from the description above. Every player gets 10 free pictures and 2 free 3D models every day (signed in with Google). Want more? That's what credits are for.
Pricing
Credits - for extra AI creations
Once today's free creations are used, credits let you keep going. A picture costs 1 credit and a 3D model costs 4 credits. If a creation fails, its credits are returned automatically.
Prices in US dollars; sales tax or VAT is added at checkout where it applies, and Paddle may show the price in your local currency. Credits are bought inside the game (Get credits) and are processed by Paddle, our Merchant of Record. Credits are a prepaid license to use REM Nebula's AI creation features: they have no cash value, can't be transferred, traded or sold between players, and don't expire while REM Nebula is running. See the Terms and Refund Policy.
Download the test build
Windows test build
- Version: 0.1 test (2026-10-02)
- Download: REMNebula-0.1-test-windows.zip, 2.0 GB
- System: Windows 10 or 11 (64-bit), a graphics card that supports Vulkan, 8 GB of memory recommended
- Price: free
Unzip it, open REMNebula.exe. Windows may warn that the app isn't recognized - click More info → Run anyway. By downloading, you agree to the Terms of Service.
Hear about the official release
REM Nebula hasn't officially launched yet. Leave your email and we'll tell you when it does - one email at launch, and the odd major update. Nothing else, and you can unsubscribe any time.
Questions
Is REM Nebula free?
Yes. The game is free to download and play, and building worlds is free. AI creation includes a free daily allowance; credits are optional, for players who want to create more with AI.
Is this the finished game?
No - this is an early test build. Things will change, some features are unfinished, and you may run into bugs. Worlds saved in the test build may not carry over to the official release.
What do I need to play?
A Windows 10 or 11 (64-bit) PC with a graphics card that supports Vulkan (most NVIDIA, AMD and Intel graphics from about 2016 on), 8 GB of memory recommended, and a few GB of free disk space. An internet connection is needed for AI creation and sign-in.
Windows says "Windows protected your PC"
The test build isn't code-signed yet, so Windows SmartScreen may warn you the first time you open it. If you downloaded it from remnebula.com, click More info, then Run anyway.
Do I need an account?
Only for AI creation and buying credits: you sign in with your Google account. REM Nebula only receives an anonymous Google account ID - not your name, email address or photo.
Who can play?
REM Nebula is for players aged 13 and older. Players under 18 need a parent or guardian's permission to buy credits.
Where are my worlds saved?
On your PC. Online sharing isn't open in the test build yet; when it is, worlds you choose to publish will be uploaded so other players can play them.
Can I get a refund for credits?
Yes - see the Refund Policy. In short: request it within 14 days of purchase through Paddle or by emailing us, and unused credits are refunded.
Contact
Questions, bug reports from the test build, or help with a purchase: email support@remnebula.com. For a payment or receipt question you can also look up your order at paddle.net.