Astral

Unreleased An Eidolon is a physical manifestation of the power of the stars that can be summoned solely by Noctis Lucis Caelum in Final Fantasy XV. Eidolons serve as the world's protectors; they defend certain areas from destruction.

Gameplay
In Final Fantasy XV, Eidolons are ranked in accordance with their size. For example, Leviathan is one of the highest-ranking and most powerful Eidolons available in the game due to its largeness. Only Noctis can call upon Eidolons, but he cannot do so in tight, enclosed spaces, such as the insides of caves. To obtain Eidolons, Noctis must defeat them in battle. They can also be obtained through other means.

List of Eidolons

 * Leviathan - An Eidolon that attacks the city of Accordo.
 * Titan - The Archaean who resides in Cauthess and plays a role in the main story of Final Fantasy XV.
 * Ramuh - The only Eidolon available in Final Fantasy XV Episode Duscae.

Creation and Development
Square Enix intended to make Titan the Eidolon that players could summon in Final Fantasy XV Episode Duscae. In the end, however, Titan was replaced with Ramuh due to the former's story significance. Ramuh's inclusion is meant to show players what happens when an Eidolon has been tamed and made available for use.