"We need fresh blood! Only a sacrifice can open this door." The dinner knife was snatched away as Kreacher excitedly shouted.
"Honorable sir, let Kreacher do it. Kreacher has plenty of blood."
"Quiet! I'll think of something," Ino softly scolded.
There were three people present, even if Sirius was ignored. With just him and Dumbledore there, letting a house-elf bleed to open the door was far too disgraceful.
Seeing the knife taken away, a hint of relief flashed in Dumbledore's eyes as he moved to the rock wall, carefully examining it.
"A low-level trick, weakening oneself to get inside. Tom misunderstood magic once again."
Unlike Dumbledore's disdain for Tom, Ino called out into the air, "Fide! Bring me my oil lamp."
Exploring with a lamp was a familiar task for him.
Ignoring Dumbledore's curious gaze, Ino had already reached the rock wall with the oil lamp.
Under the lamp's light, an extremely simple pattern appeared on the rock wall. And the reason for calling it simple was because anyone who had studied alchemy could recognize it; it was the most basic exchange ritual magic.
There was nothing profound; it just required blood containing magic, and the door would automatically appear.
Though Voldemort's method could stump many, under the lamp's light, everything was simple.
One or two runes needed to be modified to replace magic and blood with clear water.
...
"Aguamenti!"
As enough clear water poured over the rock wall, a white light flashed, and the massive rock wall split open in the middle, forming an archway.
"It's open! Young master Regulus is inside, but there are too many of them..." Kreacher ran through the doorway excitedly, with Sirius following closely behind.
As everyone entered, the hidden space Voldemort concealed finally revealed itself. But lacking sufficient light, they could only vaguely see that they were in a vast underground lake.
"A dense curse and dark magic!" Dumbledore gazed at the calm lake surface.
"Incendio!" Ino waved his wand.
Orange flames rose and rapidly expanded into a massive cloud, then split into numerous candle-like forms, quietly floating in the cave's air.
The pitch-black cave was now brightly illuminated by the star-like candles, even the farthest corners were clearly visible.
"Wonderful Transfiguration! If Minerva saw this, she would certainly award extra points."
Dumbledore looked at the sea of flames, finding it hard to believe that the once-timid student at the top of the Astronomy Tower had mastered Transfiguration to this extent in just three years.
...
In the cave, under the candlelight, countless corpses at the lake bottom simultaneously opened their eyes.
Dense bodies filled the lake bottom, mostly Muggles judging by their clothing.
But there were one or two exceptions, such as a figure in a standard Slytherin robe.
"Young master Regulus is down there, at the bottom of the lake..." Kreacher was no longer hysterically screaming; his grey eyes were filled with tears.
Seeing Regulus, Sirius felt his heart being tightly clenched, a wave of extreme pain sweeping over him.
The once obedient and well-behaved younger brother, who always followed him, was now lying permanently in the cold lake water.
Especially that Slytherin robe, it was like a heavy hammer striking his soul, reminding him that Regulus had not graduated, was not yet an adult.
"I'll bring him back! He can't lie there!" Sirius wiped the tears from his face, "It's time to go home, Regulus..."
Inferi are corpses reanimated by dark magic or controlled like puppets.
They have no life, soul, or thoughts, just the ability to act given by magic, much like the living dead in Muggle movies.
Though simple to create and not very capable individually, in large numbers, they can form a terrifying horde.
However, at this moment, the vast number of Inferi at the lake bottom were behaving like timid Nifflers, trying to hide behind rocks or in caves.
As the lowest tier of dark creatures, Inferi inherently fear fire and light, especially the star-like candles filled with hope and salvation.
...
With the suppression of the flames, everything became easier.
Sirius jumped into the water, swimming toward Regulus without hesitation.
During the retrieval process, Ino didn't pay much attention, knowing Dumbledore was standing nearby, ensuring no mishap could occur.
His focus was more on Fide, sensing Fide's joyful emotions in his mind.
Seeing the faint blue light on the other side of the lake, he didn't hesitate and used his Animagus transformation.
The black swan took off from the water, flapping its wings to fly.
On a rock on the other side.
Fide was drinking from a small puddle of murky liquid on the rock.
"I always thought you didn't eat or drink... turns out it's just about taste."
Watching the phoenix drink heartily, Ino's expression was a bit odd.
He knew exactly what the water was. It was poison brewed by Voldemort himself, its potency so terrifying that even Dumbledore had fallen into painful hallucinations.
Feeling Fide's increasing joy, Ino finally understood why the phoenix had refused his herbal feeds before.
It turned out this peculiar phoenix only consumed poison, seemingly happier the more toxic it was.
In just a few minutes, the potion in the rock had been completely consumed.
After feasting, Fide slowly flew toward the cave entrance.
Yes, flying.
Apparently, Voldemort had also guarded against phoenixes; the hidden space inside the cave not only prohibited wizard Apparition but also restricted phoenixes.
As the potion dried up, Ino found a note left by Regulus:
"By the time you read this, I will be long dead, but I want you to know that I discovered your secret and intended to destroy it..."
The message, buried for over a decade, now resurfaced, written in a youthful, somewhat proud tone, evoking a sense of the young man who once stood there.
At seventeen or eighteen, seemingly unafraid of death, he used his life to teach the feared Dark Lord a lesson.
"You should have been in Gryffindor more than Sirius."
Ino held the note, softly sighing.
He planned to help with Regulus's matter.
Though always one-sidedly reported by the Daily Prophet, it had garnered some fame.
Teaming up with Dumbledore, he believed no one in the English magical community, including Fudge, would stand in their way.
As a standard politician, Fudge, having been Minister for over a decade, surely understood the basic rules of politics: don't bully the elderly or the young.