Welp, I guess someone was being serious about a whole miniseries of games coming under the Final Fantasy XV umbrella. The Lightning Saga has yet to finish telling its story, and Square-Enix is already piecing together plans for Noctis's own saga.
The trademark "A World of the VERSUS Epic" has been filed and if you've religiously watched Final Fantasy XV's trailer, you'll find the tagline all too familiar. Have Final Fantasy XIII-2 and Lightning Returns: Final Fantasy XIII signalled the start of a new norm as opposed to being blips? Looks like it.
NeoGAF, Gematsu