ASSETS | How can I safely use third-party assets (art, music, code) in my game? – Developer Portal - Support

Developers often use third-party assets such as artwork, music, sound effects, code libraries, fonts, and development tools when building games. These assets can be extremely helpful, but developers must ensure they are used in accordance with the license terms that apply to them.

Under the Kongregate Game License & Upload Agreement, developers are responsible for ensuring that they have the necessary rights and permissions to use all content included in their games.

What counts as a third-party asset?

Third-party assets include any content that you did not create yourself, such as:

• artwork or sprites purchased from asset marketplaces
• music or sound effects libraries
• open-source code or development frameworks
• fonts or UI assets
• AI-generated assets created using external tools or services

If an asset comes from another creator or service, it is generally considered third-party content.

What should I check before using third-party assets?

Before including third-party assets in your game, you should review the license terms that apply to the asset.

Important things to verify include:

• whether the asset can be used in commercial games
• whether the license allows modification or redistribution
• whether credit or attribution is required
• whether the asset may be included in distributed software such as games

Not all assets that are available online are licensed for commercial use.

How should I handle assets from asset marketplaces?

Many developers obtain assets from game development marketplaces. These assets typically come with specific license terms (obligations). Make sure you understand and abide by them.

General & Engine-Specific Marketplaces

There are many different asset marketplaces out there for you to choose from, for 2D assets, 3D models, animations, fonts, audio including some very specialized offerings. You can easily find these yourself with some online searching, but here are a few of the more popular ones to get you started:

Unity Asset Store: A vast library for Unity projects, offering models, textures, animations, and editor tools.
Fab (formerly Unreal Engine Marketplace): Epic Games' new marketplace for high-quality assets, including Quixel Megascans.
Itch.io: A massive marketplace with both free and paid assets, favored by indie developers.
GameDev Market: Features a wide variety of 2D/3D assets, audio, and UI elements, targeting indie developers.

3D Model Specialized Marketplaces

CGTrader: A large, popular marketplace for high-quality 3D models and textures, with options to find freelance artists.
TurboSquid: Known for a massive collection of 3D models suitable for gaming and VR, ranging from free to premium.
ArtStation Marketplace: A hub for artists to sell 2D/3D art, brushes, and tutorial assets.
3Dmodels.org: Specializes in high-quality 3D models of vehicles and electronics.

Pro tips:

Review the marketplace license terms carefully
- Licenses can often change by specific assets, so be sure to check the license for each asset or group of assets
- Licenses like CC0 (Public Domain) don't require any credit to be given (no attribution needed), but many will require attribution (CC BY). Some might have non-commercial restrictions (CC BY-NC)
Maintain record of asset licenses, in case questions arise later
- Copy the license itself into the same folder as the assets you download to your computer
- Maintain a spreadsheet showing which assets you downloaded, when, how much you paid, the type of license used, and the game(s) you use those assets in. A link to the license and another link to the download page is also good to keep
Fonts can often be problematic - don't assume that they're free to use in a game just because they're included in your tools - check!
Give credit where it's due! Usually called attribution, list the creators of the assets in your game credits (some licenses require this - so check. Always nice to do even if they don't, shows you're part of the community)

What about open-source code?

Open-source software can be used in games, but many open-source licenses have specific requirements.

For example, some licenses require:

• attribution to the original author
• inclusion of the license text
• disclosure of your source code if the software is redistributed

Just like using the asset marketplaces, above, developers should review the terms of any open-source license before incorporating code into their game.

What if I use AI tools to generate art, music, or other assets?

Assets created using AI tools may still involve third-party rights depending on how the AI system was trained or how the service terms are written.

Before using AI-generated assets in your game, developers should review:

• the terms of use of the AI tool
• whether the tool allows commercial use of generated content
• whether the tool grants sufficient usage rights to the user

Developers remain responsible for ensuring that AI-generated assets included in their games do not infringe the rights of others.