Adam Cook’s review published on Letterboxd :
More Syfy Originals action but at least Dark Relic is neither a disaster or aquatic monster movie. Instead it is a supernatural action-thriller set during the Crusades as both sides join forces to battle bad CGI and a clunky script. I guess it is okay for what it is, the production values seem a little higher than normal and James Frain is better than most actors they manage to get for these films.
It tries to have a theological debate about the role of faith in our lives but this debate is incredibly heavy handed and laboured which drags the film down on numerous occasions. At least when they are battling evils (be it a poorly realised demon or possessed monks that crawl along the ceiling) it is vaguely engaging.