Final Fantasy

Final Fantasy is a multimedia franchise created by Square Enix. Although only a few entries in the series have direct ties to each other, there are a large number of recurring themes, characters, and designs that appear in multiple games and other media.

Arachne
Also known as Araune. Arachne first appears in Final Fantasy IV.

Cloud of Darkness
Could of Darkness is the final boss of Final Fantasy III.

Echidna
Also known as Hydra. Echidna first appears in Final Fantasy III.

Garuda
Garuda's first appearance was as a powerful boss in Final Fantasy III. Garuda appears as a monster girl in Final Fantasy XI and Final Fantasy XIV.

Harpy
Also known as Siren and Dirai. The Harpy first appears in Final Fantasy III.

Lamia
Also known as Hiromi, Mazalamia, and Lilith. The Lamia first appears in Final Fantasy II.

Marilith
Marilith is the boss of Mount Gulug in Final Fantasy, and is the Fiend of Fire.

Medusa
Also known as Gorgon. Medusa first appears in Final Fantasy.

Melusine
Melusine appears as a boss in Final Fantasy V.

Mermaid
Also known as Sea Witch. The Mermaid first appears in Final Fantasy III.

Queen of Eblan
The Queen of Eblan was Edge's mother in Final Fantasy IV before being turned into a monster.

Shiva
article: Shiva 

Succubus
The Succubus, also known as the VampGirl, DracuLady, or Draculady is an enemy in Final Fantasy IV.

Undine
Undine is an enemy in Final Fantasy Dimensions.