mixster

Beneath the moonlight glints a tiny fragment of silver, a fraction of a line...

(black robes, falling)

...blood spills out in liters, and someone screams a word.

**

`tiny fragment of silver' suggesting dagger, `fraction of a line' perhaps being a wire

#

"Of course it was my fault. There's no one else here who could be responsible for anything."

**

Either Quirrel or Harry. I think it's leaning more towards Harry due to his open nature with the truth, however it could be incredibly demeaning to others present, which would incline it more towards Quirrel.

#

"I do not have time for this."

**

I think repeated later on when Harry is restricted in his access of the time turner.
If not, then it seems to certainly be Harry who will say it and most likely in the middle of an important chain of events when he is interrupted by some kind of bad news or a request. I would think this would be in the midst of an experiment.

#

"Am I - could I be - maybe - you never know - if it is - but the question remains - why?"

**

Nothing seems to point towards particular characters. Given probability, I would say Harry as he is the primary `narrator'. If him, I would say that it is to do with a huge revelation (quite obviously).
A short list of these is: dark side; parseltongue and so heir of slytherin; a horcrux himself.
If not Harry, the only other person I can plausibly suggest will have a character revelation is Neville. Hermione doesn't seem the type to phrase it like this, Draco wouldn't take anything quite that nicely.

#

**Background**
"The Dark Lord came to Godric's Hollow," said McGonagall in a whisper. "You should have been hidden, but you were betrayed. The Dark Lord killed James, and he killed Lily, and he came in the end to you, to your crib. He cast the Killing Curse at you. And that was where it ended. The Killing Curse is formed of pure hate, and strikes directly at the soul, severing it from the body. It cannot be blocked. The only defense is not to be there. But you survived. You are the only person ever to survive. The Killing Curse reflected and rebounded and struck the Dark Lord, leaving only the burnt hulk of his body and a scar on your forehead. That was the end of the terror, and we were free. That, Harry Potter, is why people want to see the scar on your forehead, and why they want to shake your hand."

(And somewhere in the back of his mind was a small, small note of confusion, a sense of something wrong about that story; and it should have been a part of Harry's art to notice that tiny note, but he was distracted.

**

Why he went for Harry, which is solved by the prophecy.
The spell strikes the soul, so why was his body burnt?
What made the spell rebound?

#

"For a fee, Mr. Potter-Evans-Verres." The goblin watched him with glittering eyes. "For a certain fee. Where would you find a ton of silver, I wonder? Surely you would not be... expecting to lay your hands upon a Philosopher's Stone?"

**

Given the plot follows canon, the mentioning of the stone seems a hint for later events

#

"He's only eleven years old, Hermione."

"So are you."

"I don't count."

**

Harry assumed as other participant.
Based on major children involved, Draco or Neville seem likely targets.
Draco seems unlikely as Hermione only develops a connection later on and then it seems unlikely that she would talk of him as `weak', so I think it's more likely Neville.

#

** Not explicitly stated that it is said by McGonagall **
As his hand touched the back door's handle, he heard a last whisper from behind him.

"Hermione Granger."

"What?" Harry said, his hand still on the door.

"Look for a first-year girl named Hermione Granger on the train to Hogwarts."

"Who is she?"

There was no answer, and when Harry turned around, McGonagall was gone.

**

If not Merniva, the person who delivers the Cloak of Invisibility seems the only other plausible person. However, Minerva is later acknowledged as the person who talked to Hermione and her parents about Hogwarts, so it seems that in all likelihood it is her.

#

Suppose I told you that I met a student at Hogwarts, not already part of our circle of acquaintances, who called you a 'flawless instrument of death' and said that I was your 'one weak point'. What would you say about him?

I would say that you had been so fortunate as to meet someone who enjoys the intimate confidence of our friend and valuable ally, Severus Snape.

**



#

That sounded strangely familiar but Harry couldn't recall where he'd heard it before. "Um... you seem like a very intelligent person. Or a picture of a very intelligent person... anyway, have you heard of a mysterious game where you can only play once, and they won't tell you the rules?"

"Life," said the lady at once. "That's one of the most obvious riddles I've ever heard."

#

He peeled off the wrapper of one his meal bars and threw it into the room's rubbish bin, where it landed atop a mostly-uneaten Chocolate Frog, a crumpled envelope and some green and red wrapping paper.

...

And there also seemed to be a box, wrapped in red and green paper with a bright golden ribbon, lying next to his bed. The perfect, stereotypical image of a Christmas present, although it wasn't Christmas.
...
This is the Cloak of Invisibility of Ignotus Peverell, passed down through his descendants the Potters. Unlike lesser cloaks and spells it has the power to keep you hidden, not just invisible, though you would still be well advised to learn the Quietus Charm. Your father lent it to me to study shortly before he died, and I confess that I have received much good use of it over the years.

In the future I shall have to get along with Disillusionment, I fear. It is time the Cloak was returned to you, its heir. I had thought to make this a Christmas present, but it wished to come back to your hand before then. It seems to expect you to have need of it. Use it well.

No doubt you are already thinking of all manner of wonderful pranks, as your father committed in his day. If his full misdeeds were known, every woman in Gryffindor would gather to desecrate his grave. I shall not try to stop history from repeating, but be MOST careful not to reveal yourself. If Dumbledore realized that you possessed one of the Deathly Hallows he would certainly never allow it out of his grasp.

A Very Merry Christmas to you.

...
... A decent chunk of story
...

Dumbledore pointed to the second scrawl. "The ones in this handwriting," he said, still in that low voice, "were written by your mother. And the ones in this handwriting," moving his finger to indicate the first scrawl, "were written by me. I would turn myself invisible and sneak into her dorm room while she was sleeping. Lily thought her boyfriend was the one writing them and they had the most amazing fights."

...
... Large amount of story ...
...

My, you do get yourself into trouble and quickly. James himself was no match for you.

You have made a powerful enemy. Snape commands the loyalty, admiration, and fear of all House Slytherin. You cannot trust any of that House now, whether they come to you in friendly guise or fearsome.

From now on you must not meet Snape's eyes. He is a Legilimens and can read your mind if you do. I have enclosed a book which may help you learn to protect yourself, though there is only so far you can get without a tutor. Still you may hope to at least detect intrusion.

So that you may find some extra time in which to study Occlumency, I have enclosed 2 Galleons, which is the price of answer sheets and homework for the first-year History of Magic class (Professor Binns having given the same tests and same assignments every year since he died). Your newfound friends the Weasley twins should be able to sell you a copy. It goes without saying that you must not get caught with it in your possession.

Of Professor Quirrell I know little. He is a Slytherin and a Defense Professor, and that is two marks against him. Consider carefully any advice he gives you, and tell him nothing you do not wish known.

Dumbledore only pretends to be insane. He is extremely intelligent, and if you continue to step into closets and vanish, he will certainly deduce your possession of an invisibility cloak if he has not done so already. Avoid him whenever possible, hide the Cloak of Invisibility somewhere safe (NOT your pouch) any time you cannot avoid him, and step with great care in his presence.

Please be more careful in the future, Harry Potter.

- Santa Claus

** Thoughts **

Given what has transpired until the point, Dumbledore is the most obvious candidate for the person. The most obvious reason is that he would be the most likely one to be researching the Deathly Hallows, although a problem is thrown up in that James Potter willingly gave it to him, though this could be a lie and it was retrieved from the Potter residence along with Harry on that night. This also fits in with the author telling Harry to be weary of Dumbledore then Dumbledore directly asking him about. Given Dumbledore's intelligence, it seems unlikely he would guess that Harry is in possession of an invisibility cloak so quickly given the large range of alternative possibilities that do not require extra items and as Dumbledore quickly suggests that it is The Invisibility Cloak (i.e. Deathly Hallow), it would not be hard to stretch that he set the trap more to convince Harry that he is a good guy (by not forcefully taking it from him etc. etc.). However, Dumbledore, if not him, would also claim that it would be the Deathly Hallow as that is what a Hero should have, which is also why he would immediately jump to an invisibility cloak rather than a much more rational explanation.

Given much later occurrences, Lupin seems a prime candidate too. Being one of James' best friends and an adept wizard, researching it would seem a likely scenario. Combined with his werewolf nature, it would suggest good usage of the invisibility cloak to. Being a former Hogwarts student with James, he would of been aware of it and what James got up to using it as well as any potential warnings James would have received (such as being warned not to let Dumbledore claim it) or that he would have learnt with time (Dumbledore being quite insane and intelligent and so guess Harry's possession of it). What's more is his evident dislike of Professor Quirrel, which seems based upon his Slytherin nature. This falls into what Lupin tells Harry about why James was a bully and so, even if he recognises it as wrong, would still be prone to the bias.

Between the two, I think Dumbledore is more likely. Sneaking into Hogwarts would be possible using the route discussed in the canon books (via the little shack where Lupin went when werewolf'ing), but it seems unlikely and so someone inside the castle would have much more ease in getting it to its position (especially at a time when he is not around and without anyone noticing). What's more is there is no reason to suggest that Lupin has been following Harry's life given early questions he asks upon meeting Harry and so the very explicit detail about the pouch seems to disadvantage his plausibility at being around.

Of course, there is the third person who in no way should be involved, but has the best reasons for writing the contents of the note as well as for giving Harry a link back to his family and that is Minerva. She knows too well Dumbledore's faults and strengths as well as knowledge about Snape's skill and would want to protect him from it. What's more is that she most likely dislikes Quirrel, but puts up with him for the sake of the childrens' education, though she still wants to protect Harry from becoming evil. As to her holding the cloak in the first place, it seems unlikely and more so if she knew of James' having it while at school as both a teacher and a woman given the note regarding such.

As it is, I don't think anyone else likely. Quirrel would have no reason at all to have it in his hands in the first place. While Minerva unlikely, given the Gryffindor links she may have had suspicions which were later confirmed, though this doesn't explain the Deathly Hallows link (Lupin would most likely be aware of this though). Snape is the only other one who could be seen as having any motivation for directly involving himself in Harry's life in that Harry is still the son of the girl he loved and that link may have led to him perhaps being closer to the Potters than thought and through that link gained the cloak for experimentation (he has knowledge of electrons, which is peculiar for a wizard). However, nothing suggests this secret link and so it is very unlikely at best.

Overall, I think it most likely lies with Dumbledore else a third-party unrevealed to the story at present. Sirius being the most likely candidate for this third-party, but he's a bit stuck in prison and wouldn't know about Harry's pouch.

#

Professor McGonagall offered him a few more pleasantries, demanded a few more promises to which Harry nodded, said something about *not talking to snakes* where anyone could hear him, reminded him to read the pamphlet, and then somehow Harry found himself standing outside her office with the door closed firmly behind him.
**
Parseltongue reference disguised at as warning against what the Sorting Hat said?

#

"Even if the current Defense Professor at Hogwarts tells me that a Transfiguration is safe, and even if I see the Defense Professor do it and nothing bad seems to happen, I will not try it myself."

"I have the absolute right to refuse to perform any Transfiguration about which I feel the slightest bit nervous. Since not even the Headmaster of Hogwarts can order me to do otherwise, I certainly will not accept any such order from the Defense Professor, even if the Defense Professor threatens to deduct one hundred House points and have me expelled."

**

Specifically targeting Defense Professor, suggesting Minerva thinks ill of him or a warning about the future where he attempts to force the children to do things they don't want. Possibly a forerunner of Hermione refusing to fire on anyone else a possible reference to the wars.

#

** Peculiarly adept Dumbledore amidst the madness **

"A natural thought," Dumbledore went on, "is that since none of the first-years present were able to cast such a spell, someone else was present, and yet unseen. And if no one could see them, why, it would be easy enough for them to throw the pies. One might further suspect that since you had a Time-Turner, you were the invisible one; and that since the spell of Disillusionment is far beyond your current abilities, you had an invisibility cloak." Dumbledore smiled conspiratorily. "Am I on the right track so far, Harry?"

**

Referencing earlier comments, Dumbledore could already have all this knowledge due to him giving Harry the cloak, from where the jumps of thought become much smaller. Knowing Harry has an invisibility cloak and that he has a time turner, it makes a lot of sense that it was him, especially due to the non-magical nature of the event. Of course, Dumbledore only needed an event which suggests he could have had a cloak of invisibility, so he doesn't even need to be right - he just needs to sound plausible to convince Harry he worked it out given the circumstances rather than his inside knowledge.

If Dumbledore doesn't know, then he severely dislikes probabilities as their rareness would make it verging on the impossible of Harry possessing one. Given that, he would have to unfairly assume such. Without thinking Harry has one, the next step would more logically be that Harry found an older, more adept wizard to help him. Given that it seems unlikely he would have known about Neville being bullied before, using the time-turner to go back and get someone to help him would make the more sense. As it is, Dumbledore seems to have ignored quite a bit of logic.

His insight could be explained by his unusual thought pattern of Harry as a hero. If he assigned Harry an unique Hero quality, he would probably believe that this means he must have special items. Given the event and that Harry has a special item (apart from the known time turner), an invisible cloak is the most likely item since it explains the unknown pie thrower. This peculiar Hero quality would also explain why Dumbledore thought that Harry had The Invisibility Cloak (i.e. Deathly Hallow) rather than just an ordinary one as the probability of him having the Deathly Hallow is extremely small, even when it's given that he has an invisibility cloak.

#

The old wizard went on. "But you and I are both gamepieces of the same color, I think. The boy who finally defeated Voldemort, and the old man who held him off long enough for you to save the day. I will not hold your caution against you, Harry, we must all do our best to be wise. I will only ask that you think twice and ponder three times again, the next time someone tells you to distrust me."

**

`...for you to save the day' seems odd phrasing, like it's suggesting Harry was in training to defeat Voldemort. Perhaps looking into it too much.

Second half fits in well with Dumbledore giving Harry the cloak. By being warned, Harry has a negative image of Dumbledore, but by Dumbledore accepting Harry's caution (and explaining how he could forcefully take it quite easily, but won't), he removes the negative image and its replaced with a positive one, which is possibly stronger due to his original doubt. This all plays well for Dumbledore as Harry is much closer to him now (the "Good" side).

#

"This," Dumbledore intoned, "was your mother's fifth-year Potions textbook."

"Which I am to carry with me at all times," said Harry.

"Which holds a terrible secret. A secret whose revelation could prove so disastrous that I must ask you to swear - and I do require you to swear it seriously, Harry, whatever you may think of all this - never to tell anyone or anything else."

Harry considered his mother's fifth-year Potions textbook, which, apparently, held a terrible secret.

**

Secret being that Dumbledore wrote the notes in it rather than James. While highly disturbing, it seems like Dumbledore did that to try and convince Harry he was being entirely honest with him and sharing a harmful secret to show he trusted Harry, something he wants reciprocated.

#

...said Dumbledore. "...And this one with the golden wibblers is my own invention and Minerva is never, ever going to figure out what it's doing."

**

Sounds kinky!

#

** Doesn't say who **

"Excuse me," came a worried voice from behind him.

"I swear," Harry said without turning around, "this place is almost eight and a half percent as bad as what Dad says about Oxford."

**

Could just be a random person coming to warn Harry again about Snape.
If it isn't, doesn't seem important.

#

"Harry," Minerva said, "will you continue to submit to school discipline, or are you to be above the law now, as Severus was?"

**

Seems peculiar to say `as Severus was'. They did just agree on Snape being mean only to fifth years and higher and it seems Minerva thoroughly approves of the change, but it seems like an awfully quick adjustment, yet could just be the writer keeping things consistent with events.

#

Harry turned and fled from her office, sobbing. She heard his feet pattering away down the hall, and then the sound cut off as the door swung closed.

"I'm sorry too, Harry," she whispered to the quiet room. "I'm sorry too."

**

What is she sorry about? Is it about being disappointed, or, which I think is more likely, is she more sorry about the prophecy and what it predicts for his future, something which she may be thinking of in his presence?

#

"HE IS COMING," said a huge hollow voice that cut through all conversation like a sword of ice. "THE ONE WHO WILL TEAR APART THE VERY -"

**

Obviously, even to Harry, predicting Voldemort.

#

Who else was there for Draco now? Dumbledore? After what he'd [Dumbledore had] done? Draco would sooner have been burned alive.

**

Without the benefit of hindsight, that `he'd' seemed to belong to Draco - he being the son of a Malfoy, how could he be on Dumbledore's side? However, it clearly does belong to Dumbledore and the reference to `burned alive' a foreshadow of the future.

#

But of course if you were a Malfoy, you would be a more powerful scientist than anyone who wasn't.

So Draco would learn all of Harry Potter's methods of rationality, and then when the time was ripe -

**

Predicting a Harry-Draco stand off. Several other passages do the same, but whether it persists after some major events is unknown at the time.

#

Acts 1-6 in odd order (chapter ~26, unsure if important at all)
3: Harry `makes up' with Draco
2: Harry ponders Atlantis and magic's origin
1: Harry persuades Dumbledore to ignore the torture
5: Fred and George start the Rita Skeeter plan
6: Rita and Quirrel meet -> Quirrel implies squashing her, *sings a tune*
4: Harry `hires' Fred and George
** Doesn't explicitly state he is talking to them **
And Harry turned again and took a few more steps -

Looked back one last time, and said, softly, "Thank you."

And left.

**

Seems most likely he is just talking to them. He is quite unskilled in being gracious or apologetic, so this seems the way he would thank someone if he were to. If not, then it's possibly more just him thanking them for some other reason - I guess at being his friends.

#

As Harry left the office, he heard Professor Quirrell humming a small tune.

**

Tune reference linking this to Rita Skeeter

#

Nestled up against the wall, where Professor Quirrell had stumbled, glistened the crushed remains of a beautiful blue beetle.

**

Bye bye Skeeter

#

...meanwhile Dumbledore had happened to sneeze while passing them in the hallway, and a small package had accidentally dropped out of his pockets, and inside had been two matched wardbreaker's monocles of incredible  quality. The Weasley twins had tested their new monocles on the "forbidden" third-floor corridor, making a quick trip to the magic mirror and back, and they hadn't been able to see all the detection webs clearly, but the monocles had shown a lot more than they'd seen the first time.

**

Why would Dumbledore do this? No doubt it was a conscious act. Most likely reason is that Dumbledore thinks that, as mischief makers, they need to have good gear for doing so. Alternate reason is so that they can discover something, possibly the third floor where Philosopher's stone is kept, and report back to Harry where he can fall into his role as Hero.

#

And unless the wizarding justice system was as perfect as their prisons - and that sounded rather improbable, all things considered - somewhere in Azkaban was a person who was entirely innocent, and probably more than one.
...
You couldn't leave your home planet while it still contained a place like Azkaban.

You had to stay and fight.

**

Shows Harry contemplating the possibility not everyone, including Sirius Black, is guilty in prison. Similar to how Sirius didn't get a trial, which Harry and Hermione find odd.

#

"Um..." Harry said. "I don't want to turn anyone over to the Inquisition, but I did tell one other student -"
...
"You must swear Miss Granger to secrecy," Dumbledore said gravely. "And do not tell anyone else unless there is an extremely good reason for it, and they too have sworn."

**

Given that Harry didn't say Hermione, it seems odd for Dumbledore to assume as much. While she is the person he spends the most time with, it seems like it would have been more natural and safer to just say `swear them to secrecy' rather than naming her. It could be that, as an intelligent and powerful wizard, he feels he must say things that he thinks will make him sound more intelligent, which includes making assumptions and running with them.

#

Entirety of aftermath 2, chapter 28
Summarised by:
"Miss Cornfoot," Snape said without looking up from the sheets he was grading, "I do not return your affections, I begin to find your stares disturbing, and you will restrain your eyes henceforth. Is that quite clear?"

**

Why her? Why is this important? Is this just showing that Snape has become nicer with how he treats the younger students? Is this showing that Snape is still invading their minds?

#

An hour later Hermione had concluded that (1), Leanne and Megan were sort of sloppy, but if you asked them to keep practicing something, they would, (2) Hannah and Susan were focused and driven to the point where you had to keep telling them to slow down and relax and think about things instead of trying so hard - *it was odd to think that those two would soon be [i]hers[/i]* - and (3) she liked helping Hufflepuffs, the whole study hall had a very cheerful atmosphere.

**

Susan [Bones] assigned to Sunshine Regiment, Hannah too I think

#

"...," Harry said. "...did you know we're going to be learning the Patronus Charm? In January?"

**

Foreshadow of the Dementor events.

#

"I am wounded by your lack of trust. Well then, I promise not to help General Granger in any way that the two of you don't know about..."

**

To remove the two negatives, it does promise to help her in ways they do know about. This seems to be through the people in her army, which Malfoy figures out after the battle, in the form of Zabini.

#

"Green Forty-One standing by," Tracey Davis said.

**

Peculiar number as the other is Red Five, but probably unimportant. Forty-Two would have been the better choice, but possibly both were to be odd.

#

"Manipulative?" said the old wizard, smiling slightly. "No, manipulative would be if I did not  admit it, or if I had some deeper motive behind the obvious. This is quite straightforward, Harry. You are not yet ready to play the game, and it would be foolish to allow you thousands of Galleons with which to upset the gameboard."

**

What game is he talking about? The fight between Good and Evil doesn't seem to be relatable to money. Is he worried about what Harry could do with the money?

#

** Directly related to authors rationality work and so peculiar for Dumbledore, rather than Harry, mention it **
Dumbledore gazed out at the tables with a distant look. "In every city," the old wizard quoted softly,"the population has been divided for a long time past into the Blue and the Green factions... And they fight against their opponents knowing not for what end they imperil themselves... So there grows up in them against their fellow men a hostility which has no cause, and at no time does it cease or disappear, for it gives place neither to the ties of marriage nor of relationship nor of friendship, and the case is the same even though those who differ with respect to these colours be brothers or any other kin. I, for my part, am unable to call this anything except a disease of the soul..."

#

The old wizard favored her with a benign smile. "Why, I shall plot, of course. It's the new fashion in Hogwarts."
...
Professor Quirrell's eyes moved beneath their lids to regard Draco, and then Granger. "In truth, Mr. Malfoy, Miss Granger, I simply could not live with myself if I shut down the grand debacle before its climax. One of your soldiers has even become a quadruple agent."
...
Blaise swallowed hard. "Well... I mean, in that case... then you already know who did, right? The only one who's that crazy is Dumbledore. And he'll protect me if you try to do anything."
...
In that small, shadowy corner was a black cloak so wide and billowing that it was impossible to determine whether the figure beneath was male or female, and atop the cloak a broad-brimmed black hat, and a black mist seemed to gather beneath it and obscure the face of whoever or whatever might lie beneath.
..
Mr. Hat and Cloak gave a whispery chuckle. "Indeed," said the whisper. "With the murder of one student five decades ago being the exception that proves the rule, since Salazar Slytherin would have keyed his monster into the ancient wards at a higher level than the Headmaster himself."
...
And Blaise Zabini went on walking toward the Headmaster's office, smiling, content to be a quintuple agent -
...
And Blaise Zabini went on walking toward the Headmaster's office, smiling, content to be a quadruple agent.

**

Who could this mystery person be? They know about Salazar's pet, suggesting a Slytherin, perhaps Voldemort himself? Dumbledore believes he is at the top of the plot, so he wouldn't need to make Zabini a quintuple agent. Quirrel, although he knew before, is unlikely to be behind it as he already knew and didn't want to spoil it. As far as other teachers go, Snape is a legimens and so would need to be looking into his eyes. As a legimens, it seems unlikely he would learn memory altering charms if he could just do it via legimency. Minerva is too `good' and none of the other teachers have a reason. The one other possibility that comes to mind is another occurrence of `Santa Claus' if he indeed is a third-party.

#

"Yesss," hissed Harry, like the boy thought he was a Parselmouth.
**
Future!

#

"Mr. Malfoy," said Professor Quirrell, "your wish is for... Slytherin to win the House Cup."
...
"And for Miss Granger..." said Professor Quirrell. There was the sound of a tearing envelope. "Your wish is for... Ravenclaw to win the House Cup?"
...
Harry Potter was frowning, and something tickled at the edge of Draco's recognition.
...
"..So my own wish, to symbolize what happens when people unite in the wrong direction, is that in Hogwarts we should play Quidditch without the Snitch."
...
"No," said Professor Quirrell, "I mean that I shall grant three wishes using a single plot."

** Ponderings **

The initial solution to this that I see is that Ravenclaw and Slytherin both win by drawing. To link this to Harry's wish, one must assume the draw occurs as part of a Quidditch match and so Harry's wish is granted by Quirrel destroying the snitch mid-game or pre-game, rendering the results solely on the rest of the team. However, this does seem a bit unfair given that Harry's wish seems to be suggesting a more immediate timeframe while the other two may only be granted at the end of the year.

#

** No acknowledgement of telling Dumbledore **

"Thank you for coming, Harry," said the Headmaster. The old wizard rose from his throne, began to slowly pace through the room and the strange devices. "First, do you have with you the notes of yesterday's encounter with Lucius Malfoy?"

**

How does Dumbledore know? Most likely it's a well spread rumour, considering at least Neville directly witnessed it and his grandmother seems the type to send a warning mail to Dumbledore.

#

Yes!" said Dumbledore. "My own great foe was Grindelwald, and him  I understood very well indeed. Grindelwald was my dark mirror, the man I could so easily have been, had I given in to the temptation to believe that I was a good person, and therefore always in the right. For the greater good, that was his slogan; and he truly believed it himself..."

**

Shooting the canon Dumbledore - `Greater Good'.

#

"Okay," Harry whispered. "Happier thoughts. If you do go to a full corporeal Patronus, what do you think your animal will be?"

"An otter," Hermione said at once.

**

Seems odd how she thinks of that so quickly. Also odd how she doesn't say why.

#

"It said to me," said Professor Quirrell, "that it knew me, and that it would hunt me down someday, wherever I tried to hide." His face was rigid, showing no fright.

**

Quirrel being home to Voldemort? Dementor being death, death searching for Voldemort who defied death via horcruxes