With the release of Final Fantasy 16's second DLC expansion, The Rising Tide, the game received all of its planned content – but newer players may not get to experience the DLC until significantly later portions of the game. As a more story-oriented package than FF16's previous Echoes of The Fallen DLC, The Rising Tide focuses heavily on under-explored aspects of the original game's story and lore, centering primarily around the mysteries of Leviathan, the only Eikon to be mentioned, but not seen, during the base game's main story.

https://screenrant.com/ff16-rising-tide-dlc-unlock-story-progression/