Many regard the attempted murder of Harry Potter as Tom Riddle's biggest mistake. Others say his grandest failure was letting Albus Dumbledore live as long as he did. However, no one truly knew the most extreme slip up he had ever made.
The mistake occurred on a hot, June day, just before the sun was due to set in Tarpon Springs, Florida.
No one knew the mistake. Many years after he forgot the one detail that would permanently jeopardize his success, he held a mandatory public announcement in the small village of Amesbury. The entire population, small yet significant, attended the proclamation. The muggles having all been murdered, no one who didn't know who Tom Riddle was, now called Lord Voldemort, stood in that square. His six, most trusted followers stood to the sides of his tall, cloaked figure as he waited on the stage for the remainder of the citizens to fill in. Once they all had arrived, he removed his hood, revealing an aged face that, without the stress of committing mass genocide, could pass off as much younger. His locks remained thick and dark, sprouting a grey hair here and there.
"Now, I have gathered you all here today because I am in search of a certain pair of wizards that thought they could slip through my grasp," the Dark Lord began. "Their names are Wilfred Jordan and Lola Clebbons," he spoke out, causing a gasp amongst the crowd, some knowing them personally. The cloaked wizards standing next to their lord took notice of those who seemed familiar with the pair. "Settle down, I know you may know them. That is why you are here," he presented. "Those of you with any information will join me, give the information, and follow me for the rest of your lives... or die."
Chaos erupted in the crowd, people throwing hexes at the unbothered man who simply blocked them with a flick of his wand.
While the madness persisted, a small, cloaked figure watched from a dark corner. As people began being detained and pulled away by the followers of the corrupted dictator, the figure moved closer to the action. Lord Voldemort noticed the figure, watching its every move, entranced by its ability to move through the disturbed crowd with ease as if not seen by anyone.
"Malfoy, stop the cloaked man," Voldemort barked, watching as Abraxas began rushing to the figure. With a small wave of their wand, the person sent Malfoy soaring through the air. "Grab him!" he commanded at whoever would obey.
Moving their hands, they sent an invisible, explosive-like wave through the crowd, knocking everyone into a state of unconsciousness. Voldemort, now on his knees, watched as the magical being approached him. His breathing increased, feeling true terror for the first time.
What was his mistake, you ask? He never even realized it until the figure pulled the hood from their head, revealing the aged face of a familiar girl.
The pale arm belonging to Elizabeth Maryn stretched out, prodding the tip of her wand into his neck, "Miss me?"
For the first time, Tom Riddle felt fear... cold hard fear. In that moment, he realized his mistake. Staring up into the cold, ruthless eyes of the girl he thought he'd killed, he remembered one crucial thing about the day he ended her life:
He didn't destroy her Horcrux.