The first thing Regulus noticed was the oppressive silence of the cave. The small island Kreacher apparated him to was surrounded by murky water. The water was an ocean of darkness, of death, just waiting to embrace him.
“The Dark Lord’s arrogance truly knows no bounds,” Regulus murmured as his eyes drifted to the bone-white basin situated in the center of the island.
He pulled his wand from its holster, sending out shimmering orbs of light around the cave.
“Kreacher,” Regulus said while bending down to examine the basin. “Will the Dark Lord know we are here?”
“No Master,” Kreacher replied, glancing furtively around at the abnormally calm water. “He-Who-Must-Not-Be-Named cannot find Master and Kreacher.”
“Good, good. We may just succeed in ending his mad quest.” Regulus waved his wand over the basin.
He knew the Dark Lord delved deep into the Dark Arts, but to sink so low as to mutilate his soul? Even the Blackest of Blacks would not dare to do such a thing. Regulus frowned after he completed the last of his spells. It was impossible to reach the locket without drinking from the basin. And after seeing Kreacher’s reaction, Regulus was in no hurry to drink himself.
Regulus pulled out the fake locket, a beautiful piece that took weeks of delicate transfiguration to accomplish. After all, one can’t fool the Dark Lord with shoddy crafts.
“Kreacher, we have to get the potion out of the basin,” Regulus said as he put the fake locket away.
“Kreacher will drink again Master,” Kreacher croaked, his voice slightly trembling.
“I can’t order you to do that,” said Regulus frowning at Kreacher. “Not again.”
Kreacher looked at Regulus with acceptance in his eyes. “Kreacher is choosing to Master. Kreacher will.”
With that declaration, Kreacher snapped his fingers and a goblet emblazoned with the crest of the House of Black appeared in his hand. He scooped up a goblet full of the wicked concoction and drank it with nary a sound.
Regulus watched in fascination and horror as Kreacher slowly sank into the hellish nightmare brought about by the potion. On his fifth glass, Kreacher let out a strangled shout and threw the goblet into the water, where it sunk rapidly into the depths.
Regulus grabbed Kreacher and tapped him on the forehead with his wand.
“Somnum,” he whispered.
Kreacher sank into a peaceful slumber, his body twitching with the aftereffects of the potion.
Regulus lowered Kreacher to the floor and raised protective enchantments to surround the elf.
Regulus took a deep breath, and with one final glance at Kreacher, conjured a new goblet and began to scoop out the potion.
First drink: his occlumency barriers began tingling, something was trying to reach his mind.
Second drink: a pressure began surrounding his shields, testing his walls.
Third drink: cracks began forming.
Fourth drink: Fear Fear Fear Fear Fear.
Fifth drink: Fear Fear Fear I mUst SToP tHe DarK LoRD
Sixth, Seventh, Eighth…
The only thing that allowed Regulus to continue was the sheer force of his will. He would not allow the Dark Lord to succeed. He would sacrifice all that he is and ever could be to prevent him from reaching his goal.
Clarity struck Regulus like a blasting curse to the face. Quick, painful, leaving a mess in its wake.
The first sensation Regulus noticed was dry, parched, empty . He felt the unquenchable urge to fall into the surrounding water. Why does it look so inviting?
He clung to the scraps of his demolished occlumency shields and forced himself to look into the basin.
There, at the bottom, twinkling innocently at him, was Slytherin’s Locket. Horcrux. The Dark Lord’s key to immortality.
Regulus could sense its malevolent aura even from a distance and quickly pulled out an ancient pouch, almost humming with power. He grasped his wand and levitated the locket into the pouch.
He tightened the string and whispered, “Sigillum in nomine Reguli Astrorum, Antiquae et Nobilissimae Domus Nigri.”
The pouch glowed for a brief second and then fell dark.
Regulus could feel himself unraveling. He knew he couldn't make it out of the cave. It took all he had to ensnare the locket.
Regulus glanced at Kreacher.
He waved his wand over the pouch and then pointed it at Kreacher. “Ligatus est in magica et anima.”
The pouch vanished and Kreacher jolted awake, his eyes glowing momentarily before returning to their natural grey.
Regulus looked at Kreacher with an expression that could only be classified as a deep-seated satisfaction. “Kreacher you must get the locket out of the cave. You must destroy it.”
“Kreacher will take Master with Kreacher.” Kreacher looked at Regulus with terror in his eyes.
“No, Kreacher. I cannot leave the cave. The potion, it’s… tied me to this place. Only you can leave.” Regulus explained with acceptance slowly blooming on his face. “I order you to leave this cave and to never return, to do everything in your power to destroy the locket and end the sickness that is The Dark Lord.”
“Yes, Master.” Tears began brimming in Kreacher’s eyes. “Goodbye Master.”
Kreacher gave Regulus a deep bow, one filled with all the emotions words could not express and vanished with a pop.
Regulus looked determinately at the basin. He held his wand with a shaky hand and levitated the fake locket into the basin.
He grasped his wand with both hands and spoke one final spell: Sit Magia dona mea Request
The basin quickly filled with the vicious potion, looking as if the unfathomable struggle in mind and magic had not occurred in the preceding hours.
Regulus shuddered and collapsed to the ground. His wand slipped from his grip and rolled into the water.
He finally lowered the last of his occlumency shields.
Regulus could not think, he could not feel. His body tumbled towards the water.
The unnatural stillness hid the horror lurking underneath.
Regulus did not care.
For Regulus Black was no more.
All that remained was a corpse.