Voldemort was trapped. In a wizard's pentagram, Harry, Hermoine, Ron, Snape, and Dumbledore surrounded the evil overlord in the backyard of the Riddle house. Even now, Harry and Voldemort had their wands down, their eyes locked in an occlumency battle.
Voldemort was afraid. He had only ever had one person to be afraid of. Now he had two.
Harry was ready. Ready to do the thing that had been his fate since he was one. He was ready to kill.
The other four were silent. Their wands were up, but their attention was in the space between Harry and Voldemort. Finally, Harry spoke.
"You will die, Voldemort," Harry said quietly.
"Only one of you here can possibly defeat me," Voldemort called out, "and there is only one spell that can do it."
"We know," said Harry. That was it. His final defense, worthless. His ace in the hole, gone. His final secret, revealed. How, he did not know.
"Demons are not good secret-keepers, Riddle," Harry quietly explained.
"The spell will require a death!" screamed Voldemort.
"And I am prepared to die," said Harry. Harry's mastery of occlumency flung Voldemort backward. The pentagram shifted to encompass him. Then, as if one, the 5 raised their wands. The 4 used the Avada Kedavra curse, while the 1 chanted something else entirely. All Voldemort saw was a flash of red before Voldemort felt his life leave him.
Harry had seen the spell in action. His wand had been the focal point of the death chants while he had used the unspeakable curse. The demon's curse. The result was the body of the former Tom Riddle before them.
"It is done," said Harry. Then, there was a thump. Dumbledore lay on the ground.
A death had been required.
A life had been accepted.