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An Amateur Game Dev's Guide to Liberated Pixel Cup (LPC) Sprites

So, you've discovered the amazing, free sprites from the Liberated Pixel Cup (LPC)! They're a fantastic resource, but before you use them in your game, you need to understand their licenses. Don't worry, it's not as complicated as it sounds. This guide will explain what you need to know.

They're Free, But Not "Do Anything You Want" Free

Think of LPC sprites like a high-quality free sandwich. Someone made it for you to enjoy, but there are some simple rules about what you can do with it. You're free to eat it, change the ingredients (modify the sprites), and even sell it (use it in a commercial game). However, there are some obligations you must follow.

The core LPC assets are typically dual-licensed, meaning you can choose which license to follow:

  1. Creative Commons Attribution-ShareAlike 3.0 (CC BY-SA 3.0)
  2. GNU General Public License 3.0 (GPL 3.0)

The Golden Rules of Using LPC Sprites

Rule 1: Always Give Credit (Attribution)

This is the most important rule. You must give credit to the original creators. It's polite and required by the license. A simple CREDITS.txt file in your game's folder or a "Credits" section in your game's menu is perfect. List the name of the artist and the license used. For example:

  • Pixel Art: Liberated Pixel Cup (CC BY-SA 3.0)

Rule 2: Share Your Work Alike (ShareAlike)

This is the "catch" of the CC BY-SA license. If you modify an LPC sprite or create new art based on its style, your new creation must be licensed under the same CC BY-SA 3.0 license.

  • This rule applies only to the art. It does not affect your game's code. You are free to keep your game's source code private or proprietary. The CC BY-SA license applies to the art assets only.

This is the heart of the "open-source" art philosophy: everyone contributes and benefits from the shared work.

The Crucial Difference: Art vs. Code

This is where you need to be careful. The choice of art license can affect your game's source code, depending on which one you choose.

CC BY-SA 3.0

You are NOT obligated to share your game's source code. The license only applies to the art. You can sell your game with proprietary, closed-source code.

GPL 3.0

You ARE obligated to share your game's source code. The GPL is a strong software license. If you use the art under this license, your entire game's source code must also be licensed under the GPL 3.0 and made available to anyone who has your game. This can be a problem if you plan to sell on platforms like the App Store or Steam, which often have conflicting terms.

Important: Distributing Your Game on Stores Like Steam, Apple, and Google

This is the part that can stop your game launch cold if you're not careful. Most digital storefronts, like the Apple App Store, Google Play Store, and even Steam, have terms of service that can directly conflict with the GPL 3.0 license.

Why the Conflict Occurs

The GPL 3.0 license is designed to ensure software freedom. It states that anyone who receives a copy of your software (your game) has the right to the source code and the freedom to modify and redistribute it.

However, platforms like Apple and Google have strict terms that limit how users can obtain and distribute software. For example, they often:

  • Prevent a user from distributing the app to others outside of their official store.
  • Prohibit the user from getting the source code of the apps they download.
  • Charge a fee for distribution, which can be seen as conflicting with the GPL's goal of free software.

Because of this, if you distribute a game on these platforms that contains GPL-licensed art (and therefore your code is also GPL-licensed), you may be in a position of violating either the GPL license or the platform's terms of service.

The Safe Solution

For amateur developers planning to sell their games on these digital storefronts, the clear and recommended choice is to use the LPC assets under the CC BY-SA 3.0 license.

This license allows you to fulfill your obligations by crediting the artists and sharing your derived art, while leaving your game's code as proprietary and closed-source. This makes your game fully compatible with the distribution models of platforms like Steam, Apple, and Google.

What About Other Art? Mixing Licenses in Your Game

It's very common for a game to have art from different sources. The good news is that art licenses apply only to the specific assets they cover. The license of the LPC sprites does not transfer to your original art.

  • Your Own Art: If you create your own art (unique characters, backgrounds, effects, etc.) from scratch, and it's not derived from LPC, that art is your property. You can license it however you want: as proprietary (meaning it's exclusive to your game) or under a different Creative Commons license (like CC BY).
  • Third-Party Art: If you use art from other sources (like other sprite packs from OpenGameArt.org), you must check the license for each of those assets separately. For example, a background from another artist might have a CC0 license (public domain, no obligations) or OGA-BY (requires attribution, but not "ShareAlike").

Practical Example:

Imagine your game uses:

  1. LPC character sprites (licensed CC BY-SA).
  2. An original background you drew yourself (proprietary license).
  3. inventory icons from another artist that are licensed under CC BY (requires attribution, but no ShareAlike).

In this case, you're doing things correctly. You fulfill the rules for each license separately:

  • You give credit to the LPC authors.
  • You give credit to the artist of the inventory icons.
  • Your code is your property.
  • The background art you created is your property.
  • If you modify the LPC sprites, you must release that modification under CC BY-SA.
  • If you modify the inventory icons (CC BY license), you are not obligated to release that modification.

The key point is that the LPC's "ShareAlike" license only applies to the LPC sprites and anything you create directly from them. It does not "propagate" or apply to your original art or to other assets with different licenses.

A Final Warning: Not All LPC Sprites Are Dual-Licensed

Here's the most critical detail to be aware of. While many of the original LPC sprites are dual-licensed (CC BY-SA and GPL), many of the new assets and contributions to the LPC style that you find on sites like OpenGameArt.org may not be.

Some artists choose to license their work exclusively under the GPL. If you download and use an LPC-style asset that is only GPL-licensed, you have no choice. Your game is now considered a "combined work" with that GPL asset, and your entire game's source code must now be distributed under the GPL.

Your Responsibility

You must check the license page for every single asset you plan to use. Don't assume that because it looks like an LPC sprite, it's safe. Look for the license information clearly listed on the download page.

  • Safe to use on commercial platforms (like Steam): Assets that are CC BY-SA, CC0 (Public Domain), or dual-licensed with CC BY-SA.
  • Risk to your game's code (and store distribution): Assets that are only GPL-licensed.