Momentum arrestum III the reckoning

"Ahh!" gasps as he lands on some mushy black ropelike vines. "Whoa. Lucky this plant-thing's here, really."

"Whoa!" The plant begins to move towards them. "Oh. Ahh!" The plant ties both of them up like a rope.

"Stop moving, both of you. This is Devil's Snare. You have to relax. If you don't, it will only kill you faster." 

Yellow lightning envelops Eren, making the Devil's Snare leave him alone, with burnt vines of its own. 

Just at the sight of the Yellow lightning, the devil's snare goes rolling inwards, leaving its hostages as they were.

"What happened?"

"Devil's Snare, Devil's Scare, it's deadly fun... but will sulk in the sun! That's it! Devil's Snare hates sunlight!"

"Or light similar to the sun. I remember leaving explicit commands for you three to go back."

"But sir, we had to help," Hermione said, staring at the amputated arms for the first time. 

*sigh*

"Do not leave my sight. We do not know what are we getting into."

...

The Quadro walks down the stairs slowly. Halfway down, Harry winces, feeling his scar burning, and sees Professor Quirrell standing before the Mirror of Erised

"You- it can't be-"

"What are you doing here Quirinus? Dumbledore prohibited anyone from going past the defences as long as I could remember."

"Who do you serve Yeager?" Quirell asked without a hint of stutter from his voice. 

"But it was Snape!" Harry shouted. Eren and Quirinus looked at him.

"Foolish of you to bring children here Yeager, but who am I to refuse prey offered to myself?" He turned to Harry "Yes, he does seem the type, doesn't he? Next to him, who would suspect p-p-p-poor, st-stuttering Professor Quirrell?"

"But-but that day, during the Quidditch match, Snape tried to kill me."

"No, dear boy. I tried to kill you!" Harry eyes him in disbelief and confusion. "And trust me, if Snape's cloak hadn't caught fire and broken my eye contact, I would have succeeded. Even with Snape muttering his little countercurse."

"Snape was trying to save me?"

"I knew you were a danger to me right from the off. Especially after Halloween."

"Then-then you let the troll in!"

"Very good, Potter, yes. Snape, unfortunately, wasn't fooled. While everyone else was running about the dungeon, he went to the third floor to head me off. He, of course, never trusted me again." he turns towards the mirror again. Harry winces as his scar burns again. "He rarely left me alone. But he doesn't understand. I'm never alone. Never.

Now, what does this mirror do? I see what I desire. I see myself holding the Stone. But how do I get it?"

"Use the boy." An unseen Inhuman voice came from the back of Quirlel's head. 

"It seems you are forgetting me."

"Yeager, we don't want anyone dying here. Join us- and your mark of shame will be removed. The Dark Lord will rise once again and you will be rewarded for your help or killed for your interference."

"You ask for servitude from me?" Harry is scared at the possibility of losing his only ally in the conversation.

"The Dark Lord is fair Yeager. Join him and-"

"Yes yes, I will be rewarded, go against him and death. I understand." He turns at Harry who is looking at Eren with fear. "Will you take this Harry." He offers him his cane.

Harry takes it, while Quirrell is confused by the whole thing. 'Is he going to kneel? Why leave his wand if anything else?' 

"I do not kneel to men who lust over my freedom Quirell." Eren taps the head of his cane which is still in Harry's hands. "You chose a good position to fight in, closed places are a bad match for me."

"So you have chosen to defy him?!" Quirell's wand lights up. His master was still weak but he had to put down Yeager before the Dark Lord could be brought back.

"Avada Kedavra!" Eren pushed Harry to the left and jumped to the right. 

"Petrificus Totalus" The body-binding curse strikes Harry who is surprised by Professor Yeager having another wand, or aiming a curse at him.

"Come out Yeager. You can still redeem yourself by coming in the Dark Lord's grace." Eren pushed out the prosthetic.

Steam rose from where Eren was, or should have been according to Quirell.

"Avada Kedavra." Another green light follows the path, hitting nothing but stone. To his left was the paralysed Harry Potter. His liege's biggest enemy. But it was not time yet.

"Confringo"

"Protego" Quirell erected a defensive shield right away, but the blasting curse was not aimed at him, but on the ground below.

Quirell hits the wall with a thud but raises himself back on his feet. In front of him was the same yet different Eren.

This one had a full arm and a full leg. And his face had no scars or hint of any injury whatsoever.

"So I was not the only one hiding Yeager. The Dark Lord will bestow you a painful death for defying him, Yeager." Quirell stands on his legs again. Staring at Eren with preying eyes.

"I will do this myself." The back of Quirells spoke, and his face became pale. The eyes changed their colour to red, the nose flattened and the aura changed into something daunting.

"You have been inconsiderate Eren. I have not spared anyone who hath defied me once, but I bestow my kindness once again. Follow me and you will be rewarded, defy me and it is death you will beg for." 

The voice of the new figure was spine-chilling. Each word holds power.

"Voldemort- it is a strange name."

"You leave me with no choice Eren." The Quirrelmort raises his hand. 

"Crucio" "Expelliarmus" The red curse met its match but now for long as it reached the wand of the opponent.

Eren was blasted off due to the confrontation. While Voldemort possessing Quirrels walks slowly to his fallen body.

"There are fates worse than death in the magical world Yeager."

"Crucio" The red curse again met him. And Voldemort keeps the curse for a whole minute.