From the introduction:
The multiverse has a multitude of pantheons that rule over the different planes of existence, but those who connect themselves most to the material plane are the God’s Council. The council consists of Asmodeus, Archduke of the Nine Hells; Vecna, master lich of the Carcari; Lolth, spider goddess of the demonweb pits of the Abyss; Avandra, goddess of luck and fortune, creator of Bytopia; Melora, goddess of nature, sovereign of the beastlands; and Kord, storm god of Ysguard.
Each of these beings has an artifact weapon that grants immense power to the wielder. It is said these instruments can never truly be destroyed, but lore suggests there are ways, though they may be perilous.
The gods of the council preside over their own realms, but all have connection to the material plane where they are worshiped or feared by the mortals who walk the ground. Shrines and monuments to these deities can be found littering the countryside, and many call to these gods for help in times of great needs, or hardship.