At the spot where Dumbledore's magic wand pointed, the outline of an archway appeared on the rock wall, a dazzling white light emanating from within.
"We did it!" Sirius said excitedly.
But just as the words left his mouth, the outline vanished. Dumbledore frowned slightly, concentrating intently on the cave wall.
"Oh... so that's how it is." He muttered to himself: "It's rudimentary, but indeed effective..."
He turned to the others, saying, "I believe we need to pay a price to pass through."
"A price?" Lupin asked.
"Yes, if I'm not mistaken, it's blood," Dumbledore said contemptuously. "The person who set the trap wants to weaken their opponent in this way... so I say, it's quite a basic method."
As he said this, he conjured a short knife and rolled up his sleeve.
"Let me do it, Professor!"
Sirius stepped forward, taking the knife directly, and without hesitation, made a cut on his arm, from which bright red blood immediately flowed.
Vid wanted to speak but held back, choosing to stay silent in the end.
In his wardrobe space, he actually kept some magical creatures, most of which were gifts from Scamander and Steven Moray, with a few picked up at the maze's edge.
There were always some younglings abandoned due to illness, injury, or developmental issues that Vid rescued to enrich the diversity of species in his wardrobe space.
With magic and poppets as help, taking care of the animals or cleaning was not difficult.
Before coming here, Vid planned to find some large animals to provide blood. But upon seeing Sirius's actions, he ultimately decided not to mention it.
It wasn't that there were completely no opportunities to stop him... Sometimes sacrifice and bleeding can help shield people from inner pain.
Dumbledore did not stop Sirius. He softly recited a spell, and as the blood splattered on the rock wall, the archway appeared again.
Amidst the dazzling white light, the rock vanished, revealing a pitch-black doorway.
"It's ready."
Dumbledore said, pointing his magic wand at the hideous wound on Sirius's arm, which healed immediately.
Lupin, holding his magic wand, walked inside, illuminating the inside of the cave with light. Following him, Vid and the others also entered.
Before them lay a black lake, an endless surface smooth as a mirror, without a ripple.
Only near them did the water's surface reflect the glow from the magic wand's tip.
The darkness here seemed substantial, dense and heavy. The light from Lupin's magic wand seemed suppressed, illuminating only a small area surrounding them.
"There's such a large underground lake hidden beneath the cliff?" Lupin slowly moved his wand, saying in surprise, "Or did someone cast The Undetectable Extention Charm here?"
He saw no trace of spells around him.
"I believe it's both, Remus," Dumbledore said, his gaze fixed ahead.
In the middle of the lake, there seemed to be something, emitting a green glow, quite conspicuous amid the darkness.
"There's definitely something over there." Sirius mounted his broom, saying, "I'll fly over first to take a look. If it's safe, then you can come over."
"Wait, Mr. Black."
Vid stopped him, releasing another old broom.
"Let it scout the path first."
Under everyone's watchful eyes, the flying broom swiftly took off. Halfway through, it suddenly stopped, as if caught by a spider web, then plunged straight into the lake water.
Several pale hands emerged from the water, quickly grabbing and pulling the broom beneath the surface.
"Inferi!"
Sirius gasped, and Lupin paled slightly.
"Is this... Voldemort's army stored here?" Lupin asked.
He was not afraid to speak Voldemort's name, but in this oppressive atmosphere, his voice unconsciously lowered.
"An army? I believe they should be called Guardians," Dumbledore reflected aloud: "They tirelessly guard something for Voldemort, ready to eliminate any intruder."
"It's truly a tragedy, these people serving the one who killed them even after death," Lupin said.
Sirius snorted: "Those who delve into Dark Magic are all like that, dealing with corpses and such, reeking with an awful stench."
Vid didn't speak, carefully observing the lake's surface.
To ordinary eyes, there was only calm lake water in the cavern. But Vid could see the spell patterns densely covering the space above the water, preventing entry from above in any direction, not even a small bird could pass through.
Only one place had a hidden passage, Vid could see something glowing green extending into the depths of the lake.
Besides the Inferi, there was also an incredibly powerful curse within the lake water.
It wouldn't just rapidly weaken anyone who came into contact with it until they died, but also gradually transform any corpse that fell in into an Inferi.
This curse was far beyond Vid's beginner level, he was unable to comprehend much of it.
In the lake's center, dense magical patterns intertwined into a golden pillar of light, making it impossible for him to see the green glow visible in normal sight.
Sirius and Lupin cautiously avoided contact, each exploring in one direction before returning to say, "There's nothing but lake water."
Dumbledore had already thought of how to cross the lake, but he wasn't in a rush to reveal his conclusion, instead, he looked at Vid.