Has an AFL game ever ended 86-15?
Exactly once. On September 1, 1900, Melbourne beat St Kilda 86-15, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 86-15 in league history.
That makes 86-15 the 3836th most common final score out of 6,607 that have ever occurred in AFL. One point away, 87-15 has happened never and 86-16 has happened never.