Bazim-Gorag claimed a massive empire on the supercontinent of Merrouroboros during the latter half of the Days of Thunder. The leader of the Batrachi empires, Zhoukoudien, who had led his people to the zenith of their power, entered into a wasteful conflict with the giants to the north which decimated the carefully built up Batrachi lands. Not long later, a severe ice age struck Toril and the Batrachi, on the advice of the god Ramenos, fled to Limbo where they created the Supreme Throne. Ramenos' influence eventually caused the Batrachi to turn into creatures most sages confuse with the slaadi.
In -585 DR, Ar-magus Ilviroon summoned Bazim-Gorag to save the wizard school the Tower of the Star from a horde of trolls. Bazim-Gorag scatterd the horde but Ilviroon refused to pay him the high price he demanded. Bazim-Gorag destroyed the tower and slew several of the school's most powerful wizards as well but Ilviroon managed to imprison Bazim-Gorag underneath the tower. The next year, the horde returned, even greater in number. Ilviroon was forced to ask Bazim-Gorag to help once again but this time it was Bazim-Gorag who would refuse and Ilviroon was slain in the ensuing battle. Unfortunately, with Ilviroon, died the only knowledge of how to release Bazim-Gorag from his imprisonment.