Board Thread:False Info and Speculative Discussion/@comment-24.130.28.230-20150721180826/@comment-4091815-20160202071801

We only have the oni to consider for that question. They were stopped by mountain ash but managed to power through it. They were unable to cross in the way normal humans and other "non-supernaturals" which suggests that the sports we've seen on the show are supernatural. You might also consider that Kria has a fox sprit inside her and is unable to cross but she also has shapeshifter qualities so that example isn't as suggestive.