Seven Kingdoms: Seowyn's Crossing
The Abominations were living weapons created in the Dawn War. Some were created by the Primordials to use against the Gods, and some by the gods to fight the Primordials. The most terrible of these was the Tarrasque,crafted by the Primordials to destroy all of Tol. Happily, most of these terrible entities were destroyed, but their immortal nature means that some may yet exist.