Skirmish in the Underground Chambers

The attack in the Philosopher's Stone Chambers was a battle that took place on 4 June 1992, during Lord Voldemort's attempt to use Quirinus Quirrell to steal the Philosopher's Stone. It was also Voldemort's second attempt on Harry Potter's life.

During Harry, Ron, and Hermione's time in the chambers they battled through a set of obstacles that most eleven-year-olds would find near impossible, but succeeded anyway. In the last chamber, during the final obstacle, Harry defeated Voldemort and keep the stone safe.

The battle in the chambers was a defining moment in the Trio's years at Hogwarts School of Witchcraft and Wizardry, as they realized that their lives were never going to be normal and that Lord Voldemort would always make sure no school year would ever be ordinary.

Philosopher's Stone Chambers
There are seven chambers of the Philosopher's Stone:
 * 1) Fluffy (Rubeus Hagrid's Chamber)
 * 2) Devil's Snare (Pomona Sprout's Chamber)
 * 3) Winged Keys (Filius Flitwick's Chamber)
 * 4) Human Chess Game (Minerva McGonagall's Chamber)
 * 5) Mountain Troll (Quirinus Quirrell's Chamber)
 * 6) Potion Riddle (Severus Snape's Chamber)
 * 7) Mirror of Erised where the battle for the Stone (Albus Dumbledore's Chamber)

Fluffy
Fluffy was a giant three-headed dog, and Rubeus Hagrid's contribution to the protections put in place for the Philosopher's Stone. In 1992, Quirinus Quirrell enchanted a Harp to put Fluffy to sleep while he was searching for the Stone; when the music stopped, Fluffy awoke, and Harry Potter, Ron Weasley, and Hermione Granger had to play a Flute to put it back to sleep, before they were able to slip through the trap door Fluffy was guarding. Quirrell found out how to get past Fluffy earlier that year by enticing Hagrid into a card came, offering a dragon egg as the stake, and getting him drunk enough to disclose the secret of how to pacify the otherwise vicious dog. After the Philosopher's Stone was destroyed, Hagrid released Fluffy into the Forbidden Forest.

Fluffy may have been a play on Cerberus, the giant three-headed dog of Greek Mythology. It was a servant of Hades, and guarded the underworld.It was also put to sleep in the same way; Orpheus lulled Cerberus to sleep with his harp, just like Quirrell.

Devil's Snare


The second obstacle within the Chambers was Pomona Sprout's Devil's Snare, placed seemingly to soften a deadfall through the trapdoor guarded by Fluffy. However, as the Devil's Snare is known for strangling its victims to death, and increasing its force of constriction at signs of struggle, Hermione Granger just barely managed to save Harry Potter, Ron Weasley, and herself from death by strangulation, by attacking the plant with Bluebell flames.

Winged Keys
The third of the Chambers contained several brooms and was filled with Winged Keys, provided by Professor Filius Flitwick, which, at a distance, appeared to be birds. There was a locked door at the end of the room which was impervious to the Alohomora spell, and could only be opened by identifying and catching the one key among the "flock" that would fit the door's lock. Hermione Granger cleverly deduced that the key that would open the locked door must be an old one, to match the old lock on the door. The only old key was readily identifiable, as Quirinus Quirrell had just used it and bent one of its wings. As soon as Harry Potter, Ron Weasley, and Hermione took off on brooms to catch the winged key, they rest of the keys scattered to make the correct one more difficult to identify again. Harry was, however, able to retrieve the necessary key, which was described as old-fashioned and silver, with bright blue wings, by employing his skills as a Seeker.

Human Chess Game


The fourth obstacle was Minerva McGonagall's — a giant Wizard's Chess set. Ron took command of the game, with Harry, Hermione and himself replacing certain pieces (a Black bishop, rook and knight respectively), to defeat the opposing team and be allowed to pass. In the end, Ron sacrificed himself to allow Harry to capture the opposing King. At the End-of-Term Feast, following the events of the attack, Albus Dumbledore awarded Ron fifty House points for winning "the best played game of chess that Hogwarts has seen these many years".

Mountain troll
"I do say I have a gift with trolls."

- Quirinus Quirrell

When Harry and Hermione arrived at the obstacle set in place by Quirinus Quirrell — a troll — they realised it was already out cold. It was later discovered that Trolls were Quirrell's specialty, which he had also used to create a diversion during the 1991 Halloween feast, in his first attempt at retrieving the Philosopher's Stone.

Potion riddle
"Danger lies before you, while safety lies behind,

Two of us will help you, whichever you would find,

One among us seven will let you move ahead,

Another will transport the drinker back instead,

Two among our number hold only nettle wine,

Three of us are killers, waiting hidden in line.

Choose, unless you wish to stay here for evermore,

To help you in your choice, we give you these clues four:

First, however slyly the poison tries to hide

You will always find some on nettle wine's left side;

Second, different are those who stand at either end,

But if you would move onwards neither is your friend;

Third, as you see clearly, all are different size,

Neither dwarf nor giant holds death in their insides;

Fourth, the second left and the second on the right

Are twins once you taste them, though different at first sight."

Harry and Hermione next arrived at a Severus Snape's potions riddle. Hermione figured out which potion would help them, but there was only a little bit left. So Harry drank it and Hermione drank another one which allowed her to leave the chamber safely. Harry went on alone.

The attack
"Yes, Severus does seem the type, doesn't he? So useful to have him swooping around like an overgrown bat. Next to him, who would suspect p-p-poor, st-stuttering P-Professor Quirrell?"

- Quirrell reveals the truth.



Harry, then arrived at the obstacle of Albus Dumbledore - the Mirror of Erised. Standing there was Quirinus Quirrell. Harry was shocked - he had expected Snape. Quirrell explained that he tried to kill Harry, while Snape tried to save him. He said that he let the troll in on Halloween. He then tied up Harry and tried to figure out how to get the Stone. Voldemort told him to "Use the boy.... Quirrell summoned Harry to tell him what he saw in the Mirror. Harry lied and said it was himself winning the House Cup. An accomplished Legilimens, Voldemort wasn't fooled and told Quirrell to allow him to speak to Harry. Quirrell unravelled his turban to reveal the red-eyed and snake-like face of Tom Marvolo Riddle.



After Harry's refusal to join the Dark Lord, Voldemort ordered Quirrell to kill him, but because of Lily Evans' loving sacrifice ten years earlier, Quirrell couldn't touch him without experiencing debilitating levels of pain, and having his flesh burn. Around that moment, Harry fell unconscious due to his injuries and the pain in his scar. Dumbledore arrived moments later, and Voldemort left Quirrell's body and fled, abandoning his servant to die.

End of first year
Three days later, Harry woke up in the hospital wing to find Dumbledore standing before him. Dumbledore explained that the Stone had been destroyed and Nicolas Flamel would die. He, then, explained the reason Voldemort, and by extension Quirrell, couldn't touch him.

1995
"Yeah, Quirrell was a great teacher, there was just the minor drawback of him having Lord Voldemort sticking out of the back of his head."

- Harry Potter to Dolores Umbridge



Three years later, while explaining all he'd done to Ron and Hermione, Harry mentioned the Battle in the Philosopher's Stone Chambers. He was later given detention by Dolores Umbridge for saying that Quirrell had been possessed by Voldemort. Then, at the Hog's Head, Neville Longbottom told everyone that Harry saved the Philosopher's Stone. Then, while trying to come to the Department of Mysteries, Ginny Weasley brought up the fact that she was three years older than they were when they first fought Voldemort.

1996
"Quirrell was mediocre..."

- Severus Snape



Four years after this battle, at Spinner's End, Bellatrix Lestrange maliciously reminded him that Snape himself had interfered in the events leading up to the Battle in the Philosopher's Stone Chambers. Snape replied that Quirrell was "mediocre", and that he had stopped him simply because he was "unworthy".

Appearances

 * Harry Potter and the Philosopher's Stone
 * Harry Potter and the Philosopher's Stone (film)
 * Harry Potter and the Philosopher's Stone (video game)
 * LEGO Harry Potter: Years 1-4
 * Pottermore

Notes and references
Ataque en las Cámaras Subterráneas