Tiamat's artwork originating from Shin Megami Tensei II
"Faster than humans can fill the land... Faster than the humans can destroy the planet... I shall give birth to demons to keep them in check! So long as this land is abundant with seeds, I will birth an endless orchard of demons!"
Tiamat is the Babylonian deity personifying the seas. It is also considered the mother goddess of primordial chaos, giving birth to a number of deities that later turned against her. She is portrayed as either a sea serpent or a dragon.
"The primordial goddess of Babylonian lore. She governs the sea and gave birth to many deities with her consort Apsu, the god of fresh water. When war broke out between her and those gods, she created 11 monsters to fight with her, but they were defeated by Marduk. Her body was ripped apart and used to make the world."
—Shin Megami Tensei: Strange Journey Compendium
Tiamat is one of the four Mothers of the Schwarzwelt (alongside Maia Ouroboros, Maya, and Mem Aleph) in Strange Journey. She appears in Sector Fornax and is responsible for rebirthing Morax, Asura, Mitra, and Horkos.
She's also notable as only one of three enemies in the game capable of using the Pure Blue (a combined Dekunda-Diarahan) move, which she will only use if she has been debuffed so any of her own stats have a value of -4.
Shin Megami Tensei IV
The leader of Team Red in the Challenge Quest, RxW Smacktacular XIII. A god amongst gods, she tells Flynn she doesn't understand why the humans would participate in these games, as she was summoned and ordered by the Ashura-kai to participate rather than choosing to. Since she can't disobey, she wishes to just get it over with. After her defeat she is impressed by Flynn and admits that she never thought she would get beaten. Asking if he is Flynn and having it confirmed leads her to tell him the Ashura-kai were wary of having him participate in the games, and that things have gotten interesting before crumbling. She later becomes a common encounter in Infernal Tokyo.
Majin Tensei II: Spiral Nemesis
Tiamat is a boss in Paranoia's Tebel on the Dark-Law/Chaos routes.
Devil Summoner: Soul Hackers
"...WHY DOST THOU AWAKEN ME? I HAVE LONG FORGOTTEN BATTLE... FOOLISH ONE... THE POWER OF MAN IS NOT ENOUGH TO DEFEAT ME..."
—Tiamat, Devil Summoner: Soul Hackers
Tiamat is one of the two ancient demons inhabiting the ruins beneath Nikamimon, the other being Apsu. Their presence interfered with the Phantom Society's plans of installing Manitou at the site, so Vice-Minister Nishi hired Naomi to eliminate one of the demons to make room.
During the associated Vision Quest, the player must choose whether Naomi eliminates Tiamat or Apsu. If Tiamat is confronted, upon its defeat she curses Naomi and kills her as it dies. The goddess's power is later absorbed by Manitou, which gives it strong magical attacks but a vulnerability to physical attacks.
DemiKids Light & Dark
"A cruel, short-tempered demon who can send the mightiest demon to its knees."
