SCP:Containment Breach , legal to adapt?

Nice question, SCP: stroiresCB is a really cool game. The game is based on the stories on the SCP wiki ://www.scp-wiki.net/ The game is free so no copyrights. I think you would be able to recreate it in Unreal, that would be cool. And someone recreated it in Unity and they were fine. And the original game is already of low quality.