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We're going to destroy all seven.
It had been so easy to say those words, but reality? Reality was much harder.
It took them months of preparation - the Drink of Despair had an antidote, but it was even more sensitive and easy to ruin than Wolfsbane. Sirius spent most of the process wondering how he had ever suspected Remus, hoping that James believed him about Peter, wondering, speculating, worrying about the list that Harry had given him.
He'd long since scribbled the list on a scrap of parchment, but he had yet to share it with Regulus. If he shared it, if Regulus had all the information, would Sirius find himself relegated to the sidelines again?
The locket.
Harry had been wrong. Regulus didn't have the locket, or he didn't have it yet. What did that mean for the rest of the information?
The cup. The diadem. The ring. The diary.
Four objects that he didn't have the first clue where to look for. Two pieces of jewelry, three everyday items. Harry and the Weasleys had occasionally made reference to a diary, in connection with the Dark Lord, but Sirius didn't remember enough details to start looking for it. Besides that, the diadem was the only thing that sounded particularly distinctive. And even for that, Sirius didn't know where to start.
A riddle, Sirius had written first, and been worried about what that might even mean before he remembered: Tom Riddle, Voldemort's father's grave, that Harry had been taken to, the night he returned. Riddle, the corrected name on his parchment, must be the Dark Lord himself.
And me.
The Dark Lord would never come near the Potters, especially not Harry, if Sirius had anything to say about it. Harry would never have that famous cursed scar. He would grow up happy and healthy and mischievous, like any little boy should.
In the meantime, Sirius knew he'd missed Order meetings. He didn't remember the supposedly recent past from before Harry pushed him out of the Veil and into 1981, so he didn't remember when the next meeting was supposed to be, and invitations were by word of mouth only, so after he missed one without a good reason, he would inevitably miss several more.
October rolled into November, and the Dark Lord's reign of terror didn't falter. The Longbottoms were found dead under the dark mark less than a week after Halloween. It might be callous of him to think so, but at least they had died painlessly this time, even if it was a tragedy that little Neville had been killed alongside them.
Among all the other news, not a whisper was heard about the Potters. Sirius finally couldn't stand not knowing. He checked and found the Potters' cottage intact and still under the Fidelius, with Wormtail's dead body rotting in the open front door. Sirius stepped carefully over his once-friend, and found the rest of the house empty. James' body wasn't crumpled in front of the stairs. The nursery was empty, with no hint of spellfire, or blood, or destruction. It was surreal, seeing the house whole again, rather than the ruins he saw in his dementor-fuelled nightmares.
Hopefully no news was good news, and Peter had been left as a message for the Potters, rather than for him. Sirius apparated home from the nursery, rather than face the body again. Someone else could deal with that eventually.
And then finally, finally, the potion was ready. His seventh attempt at Liquid Hope - Sirius didn't bother to remember the proper name of it since Old Sluggie wasn't demanding it of him - was clear as ice and sparkling like a diamond, just like the recipe described it.
Sirius wondered if it was auspicious or omenous that it was the seventh batch that was good, as they began their hunt for seven - six without Harry - soul pieces. Or did it mean nothing besides that their first six batches hadn't turned out right?
They tested the antidote on Kreacher, at Regulus' insistence. The old elf perked right up, and stopped insulting Sirius to his face, though he started mixing in backhanded compliments that Sirius was all too happy to return. The sudden improvement, especially compared to the future Sirius had lived, was nothing short of a miracle.
They had finished all of their other preparations in the meantime, so when Regulus asked, Kreacher obediently took them to a cave, the entrance to which was available only at low tide. He indicated where one needed to bleed upon the wall to get through, and led them on a narrow path around the lake, and revealed the invisible boat. The brothers helped him drag it out of the water, and it arose from the deep, neatly emptying itself of water, despite having no obvious drain, as it bobbed up and began floating innocently on the surface.
Of course, that was where things quit going smoothly.
Regulus stepped into the small boat. The air around it made Sirius' neck prickle, as though the boat were deeply enchanted, but he couldn't tell the effects of the enchantment until he tried to join his brother.
The moment his foot brushed the floor - the deck? - of the boat, it began sinking before he could even put weight into it. Sirius scrambled back, stumbling on the uneven ground and landing hard on his rump on the rough stone floor.
Regulus had frozen, wide-eyed when the small boat started sinking, but he jolted into motion when a bloated hand grasped at his ankle. Regulus splashed forward and onto shore as Sirius gathered his wits enough to gasp out the spell that would cause an inferius to wither away to dust.
It worked, though with the murky lake water in the mix, the hand dissolved into a grayish mud smearing across Regulus' polished boots instead of dust that scattered in the wind.
Regulus stumbled over Sirius' sprawled feet and landed hard on the stone next to him.
"What the hell just happened?" Sirius asked.
Beside him, Regulus flexed his empty wand hand, wincing. "Nothing like that happened in your story, Kreacher." Somehow he made it sound like a question. If the same words had come out of Sirius' mouth they would have sounded like an accusation.
"That was not happening when Kreacher was last here, no it wasn't," the elf agreed.
"The boat must be spelled to only carry one wizard," Sirius realized aloud, trying not to notice the surface of the lake still churning with more inferi dragging the boat down. "One wizard, and one victim."
"No need to be so blunt," Regulus complained, then promptly insisted, "I'm going with Kreacher."
The ensuing row was held in hissing whispers, since they were both far too aware of the inferi, unsure of what, besides touching the water, might wake them. What would convince them to climb ashore and drag more victims underwater?
Perhaps because Sirius was so focused on not raising his voice, or perhaps because Regulus had finally established his own stubborn idiot streak - Regulus had been adamant even in their preparations that he would drink the potion this time, not Kreacher; and if he allowed the others to cross the lake without him, he didn't trust Sirius to make the same decision, even with the antidote ready at hand - regardless of the reason, Regulus got his way in the end. Even as he conceded, Sirius was plotting how to save his brother from himself despite the distance the lake would put between them.
At least he had talked Regulus out of leaving a note in the locket he was planning to leave in the horcrux's place. If he noticed the swap and got murderously angry, there was no need to leave a trail that just anyone could follow.
They waited until the water was eeriely still once more, then pulled the boat cautiously back up from the depths. No inferi arrived with it, and it bobbed to the surface with a perfectly dry interior just as it had before.
Regulus stepped into the boat first, then Kreacher. It remained floating. Sirius kept his distance, pressing his back against the wall of the cave, just in case. This couldn't have been how Regulus died in the first place, since Sirius hadn't been here at all, but he wasn't going to be responsible for his brother's even earlier death by drowning.
"Kreacher," Sirius called as the boat started moving across the lake of its own accord.
The old elf obediently met his eyes with a matching solemnity. This cave had put an unspoken truce to their usual petty snipes.
"Don't let him die."
Kreacher nodded deeply. "Kreacher won't," he promised.
And then they were too far away to converse. Sirius could hear the timbre of his brother's voice carrying over the water as light of Regulus' wand moved further and further away, but he couldn't make out the words.
Sirius could do nothing but pace in the meager light of his own wand. The speck of Regulus' wandlight vanished into the glow of the island in the center of the lake.
Sirius paced, and wondered what he would write to Prongs. He ought to write, especially after he had showed up on their doorstep begging them to move, and with no proof against Peter. James deserved to know what was going on. But Sirius didn't dare put anything about his current quest in writing. If word got out that the Black brothers knew about the Dark Lord's horcruces before they had finished destroying them... the family would go extinct in the male line, or perhaps entirely.
Prongs, we've finally dared make a move on the first horcrux Sirius knew he would never actually write. The first of seven pieces - really only six if you continue to stay safe.
You're my brother in all the ways that count, but Regulus is my brother too. Why did I let him go alone? I hate how Gryffindor he's become; it makes it so much harder to protect him.
If Sirius were actually writing this down, he would stop there and toss his parchment into the fire. There were more reasons than horcruces that he would never actually send these letters to Prongs.
Sirius thought he heard Regulus' voice again, but he still couldn't make it out.
C'mon Reggie you can't die. Not after I've put in so much effort to save you Sirius thought bitterly. Sure, the antidote was primarily his own effort, but he couldn't rely on that to be enough, this was his brother's life on the line.
Why couldn't that boat have carried them all?
After an agonizingly long wait, Sirius could finally see a light coming towards him from the island. That ought to be Regulus and Kreacher, but he raised his own wand defensively, just in case. He knew it lit up his face, making him an easier target if something else was coming his way, but whatever was approaching was also carrying light, so it would be equally vulnerable to him, and he could hope that nothing had gone wrong, and that this was just Regulus and Kreacher approaching.
Then he realized the light was bigger than it ought to have been, dancing back and forth, and too orange to be a simple light charm. He stared suspiciously at it, squinting to make out the details at this distance, until he realized that it was Regulus and Kreacher, just fending off something - presumably more inferi - with fire. What had set them off this time?
It didn't really matter. Sirius focused on casting tongues of flame at the assorted body parts breaching the surface near him, ensuring they didn't climb. That spell to reduce a corpse to dust worked on one body at a time, but fire would make all inferi shy away.
It wasn't as natural, when the boat got close, for Sirius and Regulus to cast their spells in syncrony the way Sirius and James did. They both sent fire to the left, leaving an opportunity on the right for a soggy corpse to drag itself up the side of the boat. Kreacher snapped his fingers and the inferius got thrown back, before Sirius could even train his wand on it.
And then Regulus was close enough to scramble ashore, without falling this time, though the flame gushing from his wand faltered. Between Sirius and Kreacher's efforts, not a single inferius crawled ashore before Regulus was casting flame once more.
It was hard to tell in the flickering orange light, but Sirius thought his brother looked paler than usual.
But that was a thought for another time. The three of them raced together, back around the lake, to the entrance which had closed. Sirius dropped his fire spell to neatly slice his left palm open, which he then shoved hastily against the wall. The wall vanished, fortunately, at the slightest smear of blood and they tumbled through, aiming fire spells behind them to keep the inferi from following.
"Get us home!" Regulus demanded, grabbing Sirius' wrist, but before Sirius could summon the focus necessary for apparation, Kreacher had grabbed onto both their robes firmly, and popped them safely into Regulus' room.
Sirius whirled anyway, taking stock of his surroundings, but there was nothing in the quiet room to justify his racing heart. No inferi had tagged along. Even his screeching bat of a mother wasn't in sight to nag them, though she probably was downstairs.
Sirius examined Regulus in the much more familiar light. Regulus was also looking around frantically but slowly calming. He was paler than usual.
"How did it go out there? Was the antidote not right? What set off the inferi?" Sirius demanded, grabbing Regulus' shoulder so they were facing each other straight on
Regulus shrugged off all of Sirius' questions and his hand. "I'm fine, we got it, Kreacher's holding it so it won't get lost."
Sirius did not relent in his efforts to assess his brother's health. "Reg," he warned.
"Here. Kreacher, give it here," Regulus instructed, holding his hand out. As soon as Kreacher handed him the locket, Regulus shoved it into Sirus' hands, a blatant, but effective distraction from his own health.
Sirius turned the gold locket over, examining the one blank side, and one with a design.
SS was engraved in emeralds, and the precise shape of it looked like...
"Slytherin," he breathed.
"What was that?" Regulus asked.
"Doesn't this remind you of the Slytherin crest?" Sirius pointed out.
"It does," Regulus agreed slowly. "Do you think all of his horcruces are relics? So that others might hesitate to destroy them even if they realize what they are?"
"Not all of them," Sirius said thoughtfully. "The diary should be much newer, but there is a diadem..."
"Ravenclaw's lost diadem?" Regulus asked incredulously. "The lost diadem of- Are you sure?"
"I'm not sure of anything, these days," Sirius admitted." But I'm sure that a diadem is a horcrux. There's also a ring, and a cup...
"Westley Smith always complained that someone stole his great-aunts chalice, inherited from Hufflepuff herself, as though he had any chance of inheriting it," Regulus recalled. "But any of the founders might have left a ring..."
"We can start with the Smiths," Sirius decided aloud. "That cup disappeared more recently than Ravenclaw's diadem."
"We can start with destroying this one," Regulus corrected. "The books said fiendfyre should work. Do you have any experience with that spell?"