The elderly house-elf nodded, but after more than a decade, all he could remember was that the entrance required blood to open, and that the hidden door was in front of him.
"Why don't we give it a try?" Ivan suggested. "I doubt Voldemort's defences will be broken so easily."
'Not a bad idea!' Sirius thought and acted, shooting out beams of light from his wand that hit the walls in front of him, creating craters.
"Split up!" Ivan tried to help, but the spell didn't work. The spell hit the wall and vanished.
Sirius and Lupin laughed. This was it!
Ivan stepped forward and looked at the uneven stone wall in front of him, remembering the scene of Dumbledore's Sensory Detection back in time, and tried to touch it too.
The walls of the cave were rough to the touch, and Ivan tried to infuse some of his magic into them, but was rejected.
This disappointed Ivan, as the spell that Voldemort had placed upon it was too advanced for him to see through.
If not for his knowledge of the plot and Kreacher's directions, he would never have been able to break through…
Ivan lamented that he had forgotten all about his little bit of self-satisfaction over his defeat of Sirius, and that he was a long way from being the Dark Lord in his prime.
"Ivan, what are you doing?" Sirius and Lupin asked curiously as they watched Ivan's actions.
Ivan came back to his senses and looked at the two of them with a puzzled expression. Without changing his expression, he casually replied, "I was investigating the movements of the magic. Since some kind of magic was used here, it must have left some traces!"
"You can detect traces of spell-casting with your senses alone?" Lupin asked, not doubting Ivan's words.
"I can't believe you've grown so much!" As much as he was impressed, he was ashamed of himself. He would never have reached this level in his life.
Ivan was momentarily embarrassed, as he hadn't actually sensed anything earlier, but had merely copied Dumbledore's casual remark.
"Ahem… then the key to open this door should be blood. Which one of us will do it?" Ivan could not stand Lupin and Sirius looking at him, so he quickly changed the subject.
"With Kreacher's blood!" the elderly house-elf exclaimed, stepping forward and grabbing a sharp piece of rock from the ground to cut his wrist.
However, Lupin reached out and stopped Kreacher.
"Hold it right there, Kreacher! You've used up enough. You'll have to get us out of here with Dobby, and you'll need to keep your magic and your strength up!" said Lupin.
"Then use my—" Sirius began, but was interrupted by Lupin.
"No! Not even you, Sirius. The spell you're about to cast will also require a lot of blood, so I'll do it this time! Don't forget, I'm better at healing than any of you!" Lupin said firmly, then placed his wand against his wrist.
An instant later, a dim light glowed at the tip of the wand.
Sirius had no time to stop the flow of scarlet blood from Lupin's wrist, and as if by magic, it flowed up the dark stone wall, dyeing it scarlet.
'Remus! It's always been about me, you don't have to do this!' Sirius sighed, upset at the loss of blood and the pallor on Lupin's face.
Beside him, Kreacher began to sob quietly. Lupin reminded him of Regulus…
More than ten years ago, it was here that it begged Regulus to use its blood to open the stone door, but the young master refused…
Ivan frowned as he watched the steady flow of blood being drawn from the wound on Lupin's wrist.
It should not have taken so much blood for Dumbledore to crack this in the original timeline…
Or did Voldemort require a sacrifice that involved not just blood, but the magic contained within it, something that Lupin's blood was far inferior to Dumbledore's in quality and therefore required more effort?
Still, it made sense.
Otherwise, Voldemort would not have risked exposure by asking Regulus for a house-elf if he did not want to sacrifice one of his own when he hid a Horcrux.
The transfusion lasted for a short while, and then a dazzling white light suddenly appeared on the stone wall, and the outline of an archway could be seen.
The remnants of the blood were absorbed, and the cave shook. The hidden door in front of them opened, revealing a doorway that was too dark to see through.
Ivan immediately cast a Healing Charm to heal the wound on Lupin's wrist.
However, due to the loss of blood, Lupin's face was frighteningly pale, and he swayed for a moment before regaining his balance.
'Are you all right, Lupin?' Sirius asked worriedly, rushing to his aid.
Lupin shook his head, indicating that he was fine.
"We'd better get going… I'm not sure how long this door will last!" Lupin warned.
His guilt mounting, Sirius solemnly patted Lupin on the shoulder, then strode through the open doorway, wand raised.
Ivan followed Sirius inside. Behind the cave was another cave, this one so large it seemed the entire mountain had been hollowed out.
In front of them was a vast, black lake, with no visible shore.
Ivan couldn't help but take a few steps closer. He squatted down and held his glowing wand close to the surface of the lake. The white light was reflected in the dead water below, but it couldn't penetrate it. All he could see was darkness…
"The water's too bad. I'm afraid it'll be hard to see if we go down there…" Ivan said quietly, trying to keep his voice as low as possible.
To be honest, he would be a fool to dive in and retrieve the corpse even though he knew there were countless Inferi down there. Unfortunately, he had to be a fool this time.
Sirius was also deeply worried, which was more difficult than he had originally thought.
Gulp, gulp …
There was a sudden gurgle of water on the still surface of the lake, and in the faint glow of the wand, pale, rotting hands emerged from the dark depths of the lake and spread across the surface…
Ivan and the others felt a chill run down their spines when they saw this. They all knew that there were a lot of Inferi, but they didn't know that there were so many of them.
"How many did Lord Voldemort kill?" Ivan asked, looking at the pale arms spread out like a pond of lotus roots, and wondering if Lord Voldemort had slaughtered a Muggle town to create an army of Inferi.
'Quick, drink it! It will hide our life force and make us as good as dead for a short period of time.' Sirius's expression changed, and he hurriedly took out several bottles of dark green potion from the pocket of his wizarding robes and distributed them.
Lupin, Kreacher, and Dobby took the bottles without hesitation, and Ivan took one, uncorked it, and gulped it down.
The dark green potion was bitter in the mouth, as if it had expired and forgotten to put in sugar coffee. After swallowing it, one's stomach felt as if it had been burned by flames, and it was extremely painful.
A moment later, the pain was gone, and a cold feeling spread through Ivan's body. He felt as if his blood had frozen over, and even his heartbeat had become very weak…