The Nephilim are giants bred by Morgan le Fay to do her will. By planting the seeds of Samyaza in the Third Circle of Hades, she was able to mass an army. The seeds grew into humanlike plant forms with a head, arms, and legs. When it was big enough, it would be uprooted and taught to walk and hate. It would then grow bigger until it was larger than any human. All of them (except Yereq) are ruthless, love to cause destruction, and serve Morgan and Mardon's orders.
YereqEditYereq was a special Naphil. He was smarter than the grown Nephilim even as an immature plant. Raised by Sapphira Adi, who gave him his name ("How about Yereq? It means 'green'.") he was taught to love, instead of hate. Morgan took Yereq away from Sapphira and taught him to hate. But although he showed hate on the outside, on the inside he still loved Sapphira. Morgan made him the commander of all the Nephilim, and had him take over training the new Nephilim. After Morgan died, Mardon took over the army. He put all the Nephilim to sleep in growth chambers, and went to the land of the living for thousands of years. During that time, Sapphira tried to wake Yereq up, but she couldn't. Eventually she succeeded, but he woke up too soon, and died. He was sent to Hell and told by an angel to battle the demons there. Later, he was brought back to Sapphira to help her on her mission.
Chazaq's job was to raise and lower the elevator in the underground labyrinths containing Morgan and Naamah's rooms, Mardon's lab, and the home of the underborns. Later, Morgan put him second in charge over all the Nephilim. He was smarter than all the Nephilim except for Yereq. After Yereq died, Mardon put Chazaq in charge of the entire army of Nephilim. In Enoch's Ghost Mardon sends him to shut down electricity for the entire country.