Eidolons are magical creatures called into battle by a Summoner. They were translated as "Summoned Monsters" in IV. Eidolons are the name of summons in several Final Fantasy games: the Nintendo DS version of Final Fantasy IV, Final Fantasy IX, and Final Fantasy XIII. The Summoners of Mist in Final Fantasy IV, the Summoners of Madain Sari in Final Fantasy IX, and the l'Cie in Final Fantasy XIII are the only people who can naturally summon Eidolons.
- Main article: Eidolon (Final Fantasy IV)
- Main article: Eidolon (Final Fantasy IX)
Eidolons are massively powerful creatures in Final Fantasy IX, with enough power to destroy whole cities. For that reason, they are targeted by people greedy for power. The people of Madain Sari are the only ones who can summon Eidolons, unless their power is extracted into gemstones. Eidolons play major roles in the game's plot. Dagger and Eiko are the only party members who can call forth Eidolons.
- Main article: Eidolon (Final Fantasy XIII)
Eidolons in Final Fantasy XIII are magical beings that can be summoned by people made into l'Cie. Each Eidolon is unique to their summoner, because they reflect the summoner's personality. They have the power to transform into mechanical devices via a system called Gestalt Mode. There are six playable Eidolons in the game, and several non-playable ones. It is said that Eidolons appear when a l'Cie's will to finish their Focus wavers.
Dissidia 012 uses the term "Eidolon" to refer to any summons from games that previously only referred to them as Summons. Even Vaan refers to them as Eidolons when facing Yuna, despite Vaan knowing them as Espers and Yuna as Aeons.
Eidolon is a Greek word for "unsubstantial image" or "phantom", additionally meaning "ideal", from which the Latin word Idolum comes. Idol is "a representation or symbol of an object of worship."