Why does Ed's cross work on the demon, but all the others don't?
Are we to believe that Ed's cross necklace is a special kind of cross?
Maybe it's been blessed. Or maybe it's the material it's made out of? I don't know.
Maybe it's the conviction he puts behind it while using it?
All we can really say for sure is that there is a distinction made between the power of his cross as compared to all the other crucifixes on the wall.
So what exactly makes his cross so special? He says it's kept him safe since he was little.