It looks like Final Fantasy 16's game engine was revealed four years ago, and no one's noticed until now.
As chronicled by one especially dedicated Reddit user, it turns out Square Enix's Creative Business Unit 3 did a talk at CEDEC 2018 in Japan, as reported by CGWorld. As we never knew what Creative Business Unit 3 was working on at the time, the talk went largely unnoticed, but now we know that the game they were talking about is none other than Final Fantasy 16, attention is being paid.
According to the article reporting on the talk (as translated by the Reddit user), Final Fantasy 16 pre-production was performed chiefly on Unreal Engine 4, which isn't exactly a massive surprise. What is a little more surprising is that after some difficulties, the game actually switched to using an extended edition of Final Fantasy 14's game engine.
This would be the Luminous Engine, which Final Fantasy 15 would also go on to use a modified version of. According to the article and talk by Square Enix staff, Final Fantasy 16 would eventually go on to significantly expand on the Luminous Engine compared to Final Fantasy 14, as Hiroshi Takai eventually switched from working on Final Fantasy 14 to heading up Final Fantasy 16.
In fact, we now know that Final Fantasy 14 is now receiving a graphical overhaul with update 7.0, when it eventually launches. There's some speculation doing the rounds, especially on the aforementioned Reddit post, that the improvements Final Fantasy 16 employs could be taken and studied by Final Fantasy 14's developers to in turn improve the looks of their own game.
Final Fantasy 16 is currently planned to launch next year in Summer 2023, while Final Fantasy 14's major patch 7.0 will undoubtedly be further out.
Producer Naoki Yoshida has hinted we could see a Final Fantasy 16 demo at some point next year before the final game launches.
