I'm making a video game with importable custom characters. My characters have a special license that forbids pornography and blasphemy in derivative works. It is viral in itself to prevent such acts.However, if someone puts a ShareAlike character such as one from Club Penguin or Floraverse into my game, does it force my game to be licensed under ShareAlike? If so, then is it illegal to mix my viral license and ShareAlike? In other words, are my characters doomed to never again be in a crossover with Floraverse characters or Club Penguin characters? Is there an exemption that I could ask from the Creative Commons license makers or the creator of Floraverse/Club Penguin?Edit:A viral license is a license that forces all derivative works to be licensed under that same license.A stained program is a program that has to be licensed under a viral license because it is stained by the content licensed by the viral license.
If I include a ShareAlike/GPL/viral-licensed character in my videogame, is my videogame stained?
license compatibility;derivative works;copyleft
The main question you should be asking yourself is: is the game a derivative of the various characters that can be imported in it?As I understand your question, the game is programmed independently and has a feature for importing characters. Characters are data. The game can work without any specific character and does not depend on any specific feature that one character is bringing. In such case, the game is not a derivative of the characters and thus its license is unaffected by the license of the characters. A fortiori, the various characters are unaffected by each other's licenses.Now, it becomes a different question if you are distributing the game with the various characters bundled in some compiled form. Then, the game (characters included) is a derivative of each of the character, and it must as such be distributed under a license which respects the various conditions imposed by each license (and you might be in a case where no such license exists because of incompatible requirements).All this being said, and even if I understood your question correctly and you are satisfied with my answer, I very much encourage you to edit your question to make it clearer what exactly you are asking (cf. Philippe's comments).