5/11/15: Just a heads up, this story is really freaking old, and definitely not my best work.
If a Muggle looked at one particular place on one particular day, in the late morning, they would see a very strange sight indeed. Over a thousand people-many of them adults-in bathrobes of various colors, fighting each other with small sticks. Yes, that would be a very odd sight indeed. Fortunately, there were no Muggles there, and if there were, they would probably be killed straight away. For, you see, a battle had just started, and everyone was, at that moment, fighting for his life.
Hundreds of Death Eaters, Dementors, and Inferi fought against hundreds of Ministry officials, Order members, and Hogwarts students.
The battle had barely started when one voice cut loudly through the air on the Hogwarts grounds. It made everyone turn in spite of themselves to look incredulously at the speaker.
"So…" came the voice of Lord Voldemort, "who are you?"
The rest of the duelers were shocked. Harry Potter had definitely did what they thought he had-
He Obliviated Voldemort's memory.
"I'm your best friend," Harry informed Voldemort, winking at the crowd. Many of the Hogwarts students sniggered.
"No he's not!" yelled a random Death Eater.
"Shut up," Voldemort barked at the offender.
"So, best friend, what were we doing?"
"Well, we were playing duck-duck-goose, until someone wiped your memory," Harry explained, looking reproachful. "And we were having so much fun!"
Voldemort's eyes burned with anger. "Who wiped my memory? They will pay! Duck-duck-goose is my all-time favorite game!"
More sniggers, as well as some barely-stifled guffaws.
"Well, he was the one who actually cast the curse," Harry said, pointing at Lucius Malfoy, "but she was the one that told him to do it," he said, pointing at Bellatrix Lestrange. Their eyes grew very wide, and they immediately began to deny it.
"Master, I would never-"
"I swear to Slytherin-"
"SHUT UP!" roared Voldemort.
"So…" Voldemort said, again talking to Harry, "how do I kill them?"
"Do you really want to kill them?" Harry asked with false concern. "Why don't you just make them your slaves or something?"
Voldemort pondered this. "I like that better," he said happily, then, "But how do I hurt them?"
"Well," Harry said, "just point that stick you have in your hand at them, and say 'Crucio'. That should do it."
"Ok," Voldemort said, pointing his wand at Malfoy. "Crucio!"
Malfoy fell to the ground, screeching. "Don't hold it too long," Harry advised Voldemort, "otherwise he'll go insane, and then he won't be able to work for you." Voldemort nodded and lifted the curse. Malfoy lay flat on his back, panting.
"Crucio!" Voldemort yelled again, this time pointing his wand at Bellatrix. After a while, he lifted the curse. "You two work for me now!" Voldemort said imperiously. "And only me!" they shrugged. "Don't take that attitude with me!" he screamed, "I am your master!"
"Yes, master," Malfoy said sarcastically from where he sat.
"Now, you," Voldemort said, pointing at Bellatrix, "you must brush my hair while I talk to my best friend."
"Er…master?" she asked tentatively.
"What?" Voldemort snapped.
Voldemort shrieked like a little girl. "What do you mean, bald?"
"You don't have any…"
"I know what bald means, slave, grow me some curly blonde hair! NOW!"
"You had straight black hair before," Bellatrix informed him quietly.
"Fine, fine, straight black hair then! I want to talk to my best friend here!"
Bellatrix pointed her wand at Voldemort's head and muttered a spell. Hair began to grow. "How much, Master?"
"Elbow length, so you can braid it into pigtails," Voldemort said gleefully.
The watching crowd did not bother to conceal their laughter. Voldemort glared at them, however, and they shut up.
"Righty then," Voldemort said, squatting down on the ground, "How do I get my memory back so we can play duck-duck-goose some more?"
"Well, if you stand still and don't move, I can cast the spell for you," Harry said, attempting to keep a straight face as Bellatrix impatiently plaited Voldemort's hair into pigtails. "Do you want me to do it now?"
"No, after my other slave finishes my manicure and pedicure. Slave #2!" he yelled at Malfoy, "Come over here and fix my nails! They look dreadful!"
Rolling his eyes, Malfoy walked over and proceeded to do Voldemort's nails. "I want them painted pink, slave!" Voldemort roared at him.
Harry noticed that many of the Hogwarts students had conjured up popcorn and had sat down on the grass to watch, grinning.
Finally, Bellatrix was finished. "How do I look?" Voldemort asked Harry, concerned.
"You look wonderful," Harry lied convincingly. In actuality, seeing Voldemort in pigtails and pink nails, or indeed, Voldemort not attempting to kill him, was rather disconcerting.
"Now, restore my memory, best friend," Voldemort told Harry, "So we can play some more."
"Right away," Harry said, smiling. He pointed his wand at Voldemort, "Avada Kedavra!"
Voldemort, still smiling serenely, with pigtails and a manicure, fell over backwards, dead as a doornail. However, that was not to be the last they saw of Lord Voldemort-his spirit appeared flying upward. He was, once again, shrieking. "Pink nails and pigtails?" he screamed, then disappeared into the sunlight.
Immediately all of the Death Eaters attempted to flee, but the Aurors caught them and sent them to Azkaban, which was now guarded by pixies. This was very effective, as they terrified most of the prisoners out of their wits just as much as the Dementors did.
Everyone celebrated in the Great Hall that night, and Harry was given a new title- "The-Boy-Who-Defeated-He-Who-Must-Not-Be-Named-Using-A-Memory-Charm." Or, the abbreviated version, "The-Boy-Who-Conquered." Usually, people used the latter.
"Why'd you use a memory charm, though?" Seamus asked Harry later that night.
"Dunno," Harry answered, grinning. "First thing that popped into my head."
Their party lasted well into the night, until Dumbledore finally made them go to bed at 4 am. By that time, Harry was in slight withdrawal.
"Cheer up, Harry," Ron told him, "At least you stuck to your word!"
"How so?" asked Harry glumly.
"Did you see his face when he found out he had pigtails?"