Harry had just revealed that he was the True Master of the Elder Wand, and he knew it was almost time. He watched carefully, waiting for the curse that he could see was on the edge of Voldemort's lips. He watched, as if in slow motion, as Voldemort's arm was raised in tandem with his own when suddenly a huge pillar of what seemed to be black shadow rose up between them. Out of the shadow came a teenager, a boy with black eyes and hair dressed in all black and an aviator jacket who looked like a living skeleton if there ever was one. Harry watched, confused, as the boy turned straight towards Voldemort holding a large black sword and yelled, "Tom, stop!"
Harry watched in amazement as he saw Voldemort pale (who knew he could get whiter?), and stumble backwards. He desperately wanted to pinch himself to see if this was real when he heard Voldemort stutter, "N-Nico?"
He was surprised at all the emotions he could hear in that stutter, but he was shocked when he recognized hope. Then he realized that the two were speaking in parseltongue, and never had he wished more that he could still understand it. He was dying to know who this teen was, how Voldy knew him, and why the hell he was acting like a bloody sixteen year old.
But he couldn't, so instead he sat there and watched with the rest of them as this boy, Nico, walked towards the Dark Lord while having a conversation in parseltongue. Voldemort looked as if a dream had come true but didn't dare to believe it. He got the shock of his life when, when Nico was only a few feet away, Voldemort moved forward, so fast hardly anyone saw it, and suddenly the teen was being embraced by the most feared Dark Lord in over a century. Everyone stared, dumbfounded, as they continued to speak to each other in parseltongue, still embracing each other. Harry watched as they grinned at each other and Voldemort kissed the teen, and he faintly registered the thumps of more than a few people fainting.
Harry watched as the shadows started to envelope the pair. A moment before they disappeared, a loud crack! echoed through the room and Harry found himself staring at the shell of the man who was his greatest enemy with no recollection of the teen and a new set of memories.