The god Destroyer

The Queen of Air and Darkness wanted a weapon to kill the god Corellon. She worked with Bane the god of war to fashion a sword so great that it could make a god Mortal. The weapon was forged in several parts. However Moradin, god of creation caught wind of the weapon being forged. He, Bahamut and Corellon were able to obtain the weapon. They broke it down into 4 parts and separated them.

The Hilt Bahamut gave to the Gold Dragons to protect. Ancient Golden Dragon named Gildon. Stolen by Ducia
The Guard - Protected by Storm Giants but legend has it was stolen by a legendary halfling pirate of the Sword coast named Captain Silbarr Snake-Eyes. His treasure has been lost to time.
The Blade - Many ages ago the Titan Empyrean named Zaphiel was entrusted with the blade. Just before the age of Humanity, about 5,000 years ago, Zaphiel's trusted warrior, Crawthux became corrupted. In an epic battle of the titans, Crawthux slew Zaphiel. Crawthux's form became more twisted and corrupt and he took the blade to his lair deep in the ocean.  Crawthux is known by a differnt name, Slarkrethel.
The Pommel - the ring of winter.