The new angel of death had released uncontrolled energy and that's why the current time is known as "A.S. - After Sundering" And everything else is known as "B.C. - Before Crisis"
And again, he killed more than he was instructed to. He continued to do so until the population of mankind was reduced to 1/3. Furious God punished the angel of death and banished him from heaven
Realizing what he had done, he refused to kill again. With the job being only half done, God sent a new angel of death to earth to finish things. This new angel of death basked in the glory of his duty.
1000 years ago demons managed to cross over onto the earth realm using willing humans as a portal. God sent the Angel of Death to begin slaying people who were helping the demons.
I remember I was going to make a game once where the hero saves some kid early on in the game, then at the end of the game the hero dies and the kid grows up and you play the kid that was saved in the sequel