Hello, I live in Ontario, Canada but the game is published in Europe and North America.
We only handle US law questions on this site, 3dArtist. Sorry.
Although the IP laws in our two countries are similar, they are not the same. Even if your game has worldwide distribution, if you are sued over your game, you will be sued in an Ontario court under the laws of Canada.
For one example of why the laws in the US will be of little use to you: In the US, a First Amendment defense has been used with success in a few trademark infringement claims (one game-related trademark infringement case decided in favor of the video game publisher last November). But there is no First Amendment defense available for you to use in Canada so our case law will be of no benefit to you.
Anyway, ALL cases are fact specific, so a personal review of your specific game, and how you are using (or intend to use) the rights-protected material of others, would need to be done by a professional in your area. Even if there is a chance you could win a lawsuit filed against you, however, it is still smartest to get permission from any rights-holder prior to any use of protected material. It is best not to be put in a position where a court must decide your fate.