It had taken a great many rather dubious alterations to the castle's plumbing through the Map Room's magic, but Oleandra was fairly certain she had at last contrived a way to reroute the ley lines' power through the pipes and into the Grand Staircase.
In a rather unexpected turn of events, it was the Chamber of Secrets that had given her the idea. To maintain its enchantments, Salazar Slytherin had secretly installed what could only be described as a "back door," allowing him to siphon off the castle's magic and redirect it to the Basilisk's lair, and finding the notion altogether too sensible to ignore, she had decided to borrow the principle for herself.
What magical circuits are to Wizards, ley lines are to the planet; they carry telluric magic from the planet's core and distribute it across the earth, which is why they are called dragon veins in the Orient. Following the principle that all things must flow from high-pressure environments to low-pressure ones, Oleandra had made it so that at a moment's notice, the castle's plumbing could turn into conceptual ley lines… empty ones, that is.
Under normal circumstances, magic from the telluric knot would accumulate in the silver repository beneath Hogwarts and be distributed as needed to sustain the castle's eternally lasting magics… but if a dried-up ley line were suddenly linked to that very repository, it would draw in all its stored power in a single greedy instant and discharge it at its opposite end… which would be the bathroom at the bottom of the Grand Staircase, if Oleandra hadn't made any mistakes.
In Muggle terms, it would be rather like shorting a circuit; when a difference in potential exists, the current will always prefer to avoid resistance and take the easiest path available… and Oleandra planned to duel Loki exactly where that power would discharge. Of course, just like a short circuit, Oleandra's little stunt would very likely fry some of the ancient castle's more delicate enchantments, but that was a sacrifice she was prepared to make.
And so, content with her alterations, Oleandra fell asleep in the Map Chamber late at night, but what she had intended to be a brief nap ended up lasting far longer than she had planned. She awoke the following day, October 31st, towards three-thirty in the afternoon, feeling unusually refreshed… until her eyes fell on her watch.
"I overslept!" she shrieked, startling the four Keepers' portraits. "The feast!"
Oleandra leapt to her feet and spun on the spot, vanishing in a swirl of blue feathers before reappearing in her dormitory room.
Though she had removed the additional restrictions that Dumbledore had imposed to prevent her from using Tree-Portation within Hogwarts, she had seen no need to lift the Anti-Disapparition Jinx, since her teleportation abilities did not stem from training but from draining a Diricawl's powers; in other words, just like House-Elves, Hogwarts's wards could not hinder her from coming and going as she pleased by tearing her way through space-time.
"It's now or never, I suppose," Oleandra muttered to herself, reaching into her magical pouch and retrieving the first of the two golden bottles she had stashed within it. "Down the hatch!"
Without hesitation, Oleandra tossed back her head and drained the tiny bottle in a single gulp. To her tastebuds, the golden liquid within tasted rather like apple crumble, with hints of cinnamon, caramelised sugar, and roasted walnuts. As the flavour faded from her tongue, a strange sensation washed over her… as if she were observing herself from a third person's perspective, but from her own eyes. She remained in full control of her body, yet it felt as though she had let go of the metaphorical reins and handed them over to a perfect version of herself.
Bursting with newfound confidence, Oleandra straightened her posture and marched from her room. She slipped into the file of Slytherin students leaving the common room, walking with them as they ascended from the dungeons past the toilet she had modified, and climbed the Grand Staircase… but when they reached the Reception Hall, instead of turning right with them towards the Great Hall, she veered left into the Entrance Hall and strode straight out of the castle.
Oleandra froze in her tracks, one foot poised in midair as she teetered on the verge of descending the front steps. Just where on earth was the Felix Felicis leading her!?
"This isn't where I need to be," Oleandra called to no one in particular.
She loosened the reins, and her foot came down… she was still going down the steps.
"No!" Oleandra growled. "I am not running away!"
Was this what the potion was trying to tell her? That if she went through with her plan, no luck in the world would be able to save her from the consequences? That her best course of action was to run as far away as possible, to leave and never look back?
Ignoring the instincts screaming at her to keep going, Oleandra turned and walked back into the castle, making her way to her seat at the Slytherin table in the Great Hall, directly in front of a smiling Daphne. She would never know that, had she only trusted the Felix Felicis, she might have met Astoria by the lake and enlisted her help in the upcoming battle… and learned from her that Daphne was no longer Daphne.
"I was looking for you, Oleandra," Daphne said reproachfully. "Where were you last night?"
Her eyes fell on the black stone set in the ring on Oleandra's finger. It was no longer cracked; Oleandra had repaired it with the Elder Wand, so she noticed nothing amiss.
"Someone's in a good mood," Oleandra replied, steering the conversation away. "Has something good happened to you lately?"
"Something like that," replied Daphne.
Although Oleandra longed to steal a glance at Loki, her instincts told her the moment was not yet ripe. The opportunity to draw him away would come later in the evening, when everyone was busy tucking into pumpkin pie.
Instead, as if pulled by some invisible magnet, Oleandra's gaze settled on Tracey.