After getting through the large chessboard, Neville and the others realized what Quirrell's defense was.

Neville was at the front, pushing the door open, and a disgusting stench came over him. Harry and Hermione lifted their clothes to cover their noses, and even then their eyes were filled with tears.

"This stinks like ......"

Through the blur of teary eyes, they saw a troll, even larger than the one they had fought last time, lying motionless on the floor in front of them, unconscious, with a large bloody lump on its head.

"That's what Professor Quirrell laid out. "Neville Road.

"Great, we don't have to fight this troll anymore. ”

Harry whispered, this level could save a lot of time. It's just that based on the previous situation, the next level should have been arranged by Snape, and hopefully it will still be a level that Neville can push through.

They quickly straddled the troll's thick legs, and the stench of damage was apparently high compared to the troll's massive size.

"Let's go, I'm out of breath. ”

Pulling open the next door, the next room was surprisingly shabby: there was only a table with seven bottles of different shapes lined up.

"Snape's magic. Harry said, "What should we do?"

No sooner had they crossed the threshold than a flame rose from behind them, sealing the doorway. The flame was unusual, purple. At the same time, black flames burst out from the doorway to the front, and they were trapped in the middle.

"Look!"

Hermione grabbed a roll of parchment that had been placed next to the bottle, and Harry and Neville stood behind her, looking at the contents of the parchment together.

It looks like it's a puzzle,

"Danger is in sight, safety is in the rear, and two of us can help you.

Drink them down, one will lead you forward, and the other will send you back to where you came.

Two were filled with nettle wine, and three were killers, waiting in line.

Choose, unless you want to be here forever.

We also provide four clues to help you choose:

First, no matter how cunning the poisons may be, they are always on the left side of the nettle wine;

Second, the contents of the bottles at the left and right ends are different, and neither of them will work for you if you want to move forward;

Thirdly, you will find that the bottles are of different sizes, and that there is no Grim Reaper hidden in the giants and gnomes;

Fourth, the second on the left and the second on the right, although the appearance is different, the taste is the same. ”

After reading this question, Neville looked confused, Harry was better than him but not much better, only Hermione Hermione let out a long sigh and actually smiled.

Glancing at Neville, Hermione said, "Great, it's not magic - it's logical reasoning - it's a riddle." Many of the greatest wizards have no ability to reason logically, and they are trapped here forever. ”

Neville scratched his head and pulled a small notebook out of his pocket, an act that caused Harry and Hermione to stop talking. They looked at Neville and his little notebook with strange eyes, could it be that he had the answer to this question in his little notebook?

However, Neville only flipped to the blank page, wrote and drew on it with his pen, and whispered the title on the parchment.

"Well, this question needs to be memorized, and maybe you will be able to use it later. ”

For some reason, Hermione felt a lot more relaxed, and this time she finally had a chance to stand out. But hurry up, because by the time Neville finishes copying the questions, he'll probably be going to do something that drives all the self-proclaimed smart people crazy.

"All we need to know is written on this piece of paper. Seven bottles: three for poison and two for wine, one to pass us safely through the black flames, and the other to send us back through the purple flames. ”

Holding the parchment, Hermione frowned, devoting herself to solving the problem. As most people agree, she is indeed a very intelligent girl, and the answer to this question is obvious after she dismemberes it one by one, and after extracting useful information.

From these conditions given in the title, it can be inferred that:

1. Poison and medicine on the left side of nettle wine;

2. The left and right sides are not the same liquid, and neither is a potion capable of moving forward;

3. The largest bottle and the smallest bottle, that is, the black bottle and the blue bottle, are not poisons;

4. The second on the left and the second on the right, that is, in the red bottle and the black bottle, are the same liquid;

5. Of the seven bottles, there were three bottles of poison and two bottles of nettle wine, one forward, and one returning. ”

Then, the following conclusions can be deduced:

Conclusion 1: According to condition 1, there is no poison in the purple bottle, because there must be nettle wine on the right side of the poison;

Conclusion 2: According to Condition 2, the brown bottle and the purple bottle are either poison, nettle wine, or return medicine, and according to Conclusion 1, the purple bottle is either nettle wine or return medicine;

Conclusion 3: According to condition 5, only the number of poisons and nettle wine is more than two bottles;

Conclusion 4: According to conditions 4 and 3, the red and black bottles are either the same poison or the same nettle wine;

Conclusion 5: According to Condition 3, Conclusion 1 and Conclusion 3, the black, red, blue and purple bottles are not poisons;

Conclusion 6: According to conclusions 4 and 5, nettle wine is in red and black bottles;

Conclusion 7: According to Conclusions 5 and 6, the elimination method was used to know that one of the blue bottles and the purple bottle was the advance medicine and the other was the return medicine;

Conclusion 8: According to Conclusions 2 and 7, the blue bottle is the advance medicine, and the purple bottle is the return medicine.

Hermione read the piece of paper a few more times, and she walked up and down the row of bottles, muttering to herself as she pointed to this or that bottle.

Finally, she clapped her hands happily.

"Got it," Hermione said, "this smallest bottle will help us get through the black flames and get the Philosopher's Stone!"

Pressure is also motivation, and before Neville's question is finished, Hermione has already found the answer, which can be regarded as a super-level performance.

Harry picked up the humble little bottle, looked at Neville and Hermione, and said, "There's only enough for one person to drink, less than a sip." ”

"Something is wrong. ”

Hermione's eyebrows furrowed again, she looked at the smallest bottle, and said puzzledly, "If this level is to stop the thief from moving forward, why do you put the advance medicine here? someone has already come in before us, and we haven't met him until now, then he should have passed this level too, why is there still a medicine left here?"

"Because that thief is Snape!"

Harry said loudly, a little upset, because Hermione still didn't seem to believe that Snape was the thief, but here was the evidence.

"Since Snape is a thief, isn't it normal that he will definitely leave the back door and prepare a medicine for himself?"

"But if Snape is a thief, then what is in this bottle is really the medicine of the advance, and it makes sense that he would change the potion before he gets here, so that no one else can come in and stop him. Hermione said, showing Harry the parchment in her hand, "It's impossible for someone who can come up with such a topic not to think about it!"

"This ......"

Harry looked at the potion in the bottle, but the joy he had felt was gone, if the potion in the bottle had been replaced by Snape, and it was not a propulsion, it would have been really bad.

"What are you talking about?"

At this point, Neville, who had finished copying the question, spoke. Harry told him everything, but he didn't expect him to come up with a solution, but Neville did give him a solution.

"Well, that's easy. ”

Neville took the bottle from Harry's hand, snapped the cap off with a flick of his fingers, and then raised his head to drain the potion from the bottle. The potion tasted like a cold soda, and the coolness permeated his whole body at once, and there were flames burning in front and behind, and the temperature here was much higher, but Neville didn't feel the heat at all now.

"You ......"

Hermione pointed at Neville, anxious and annoyed, unable to speak. Before, he was glad that Neville didn't show enough behavior to drive smart people crazy, but in the blink of an eye, he did it.

Harry was also taken aback, and quickly asked, "Neville, are you alright?"

"I'm fine. Neville replied, "This bottle should be real, I'll have to hurry up and test it to see if it works." ”

Harry couldn't help but roll his eyes, holding the empty bottle to Neville, and said, "I don't think there's a need to test it, even if it's really a procurator, but now there's not a drop left." ”

The only bottle of suspected advance medicine is gone, and there is no need to worry about whether it is really a advance medicine or not, because it is meaningless.

Neville looked confused, as if he had done something stupid again?

"What then?" he asked.

"Let me think about it. ”

Harry felt tired and helpless. Obviously, there is a solution, just let Neville go through the Flame Gate to get the Philosopher's Stone back, but the question is if there is still a problem in the next level, can Neville solve it?

Then again, Harry didn't care about the thief who had infiltrated before them, he had too much faith in Neville.

Neville, who got serious, was really a big mess!

But this thing often makes mistakes, and it's a hard injury to do things that make people speechless.

"Forget it, we'll wait for you here, you go over first and see if you can get the Philosopher's Stone back. Harry could only pin his hopes on Neville, "Also, be careful, Snape should already be there." ”

"I'll definitely bring back the Philosopher's Stone!"

Neville looked scrappy, which was good, but Harry and Hermione couldn't be reassured at all, and could only watch him walk towards the black flame door.

Taking a step forward, Neville could see the black flames licking his body, but he didn't feel it. At that moment, he couldn't see anything, only black flames in front of him. Then he went to the other side and entered the last room.

It's just that there's no one here, no Snape, and no Voldemort.

In this large, empty room, there was only one mirror.

If Harry had been here, he might have recognized the mirror as the Mirror of Eris that he had found during Christmas, but he didn't expect it to be here at this time.

No enemies, no exit for the next level, no hints......

Neville looked at the mirror and scratched his head, let's go over and see what it was.