The Royal Edition combines the original game with all of its Season Pass content, which includes Episode Gladiolus, Episode Prompto, Episode Ignis, and the multiplayer expansion Comrades. However, this version of the game goes further than that, bringing a few extra features even for previous players.
The map has been expanded to include a new dungeon in Insomnia City Ruins, and a number of new bosses have also been thrown into the mix. You'll also be able to captain the Royal Vessel and explore the sea between Cape Caem and Altissia. Additionally, there will be a first person mode, new gear, and more besides. This sounds like a pretty generous deal, honestly, offering lots of extra stuff for both new and old players.
However, if you do already own Final Fantasy XV, the Royal Edition extra content comes in at $19.99 as a separate purchase, which is perhaps not so generous. If you're interested, Final Fantasy XV Royal Edition will release on 6th March, so there's not too long to wait.
Will you be treating yourself to the Royal Edition? Are the extras worth the extra dosh? Sail the Royal Vessel into the comments below.