What grammatical concepts are behind そうな at the end of a sentence? In , at least the version I am looking at, one of the opening lines is: > **** I can't figure out how to explain the bolded part. would either mean "seems like" or hearsay. Based on the conjugation of the preceding verb I conclude that we're dealing with hearsay here, which would fit the tone of a folk tale. But I'd then expect or . The only possible explanation I can come up with is that the is omitted, and then we're left with as a sentence ending particle.

is the pre-noun form () of . It is an instance of , which (according to the linked Wikipedia entry) became common in 14-16C.

Using at the end should be an (pseudo) archaism that is commonly seen in starting folklores.