Tiamat (Pronunciation: TEE-uh-mat), also known as the Polychromatic Dragon or the Daughter of Io, was an Astral Being born from the two halves of Io’s body. She is said to have had five heads resembling the Red Dragon, Blue Dragon, Black Dragon, Green Dragon and White Dragon; three tails based on those of the Purple Dragon, Brown Dragon and Gray Dragon; and four wings resembling those of the Orange Dragon, Cyan Dragon, Yellow Dragon and Magenta Dragon. She also had the front limbs of the Indigo Dragon, a mythical dragon with incredible strength and invincibility; and the hind limbs of the Tan Dragon, another mythical dragon said to possess the gift of all four kinds of magic.
In the Origin of the Twelve Dragons of Atonus, the dissident within Corellon’s Elvenkind of Old shattered the Astral Continent, separating it into a multitude of islands which drifted apart across the Astral Sea. Tiamat was right in the middle of the crossfire, and her body was ripped to shreds, with each section forming into a shard of coloured crystal. Twelve dragons were selected to each guard a crystal, and the process transformed them into a collective of Astral Beings known as The Twelve Dragons. This disaster forced the remaining Astral Beings to draw power from the Elemental Chaos in order to form a new world, as the Astral Sea could no longer accommodate the growing population of mortal beings.
The Metallic Dragon Senates know of an additional chapter in which two more dragons came across metallic shards, leftover fragments of Io, and became Astral Beings themselves. Many members of the other Races, particularly the Chromatic Dragons, don’t worry about the extra chapter, as they each worship a particular member of The Twelve. The people of Wieva pay tribute to Tiamat, as their pointless war saw her demise. The Half-Elf race in particular honours the entire collective of The Twelve, for their birth also saw the birth of the Half-Elven people.