Tiamat, Dragon Goddess

A mix of Dungeons & Dragons' Tiamat, sans chromatic entourage, and the Sumerian goddess of creation. I had this idea that she would 'birth' more and more deities but they'd become fused with her body, causing her to grow in size and strength. Finally when Marduk finally slays her she would split into the heavens and the earth, filling the world with all of the story and mythology of the old gods and goddesses.