The fight at the Ministry had gone to shit. It started when an owl with a note showed up, informing him that the sender—one Theodore Nott Jr.—had taken his girlfriend of four years—Luna Lovegood—hostage. If he wanted her back in one piece, he would have to make his way to the Hall of Prophecies within the Department of Mysteries within the next half hour, without informing staff, or Nott would kill her and feed her corpse to Fenrir Greyback.
Knowing it was an ambush but unwilling to risk Luna's life, he acted without hesitating, calling an emergency meeting of the Defense League, where he explained what he knew. They all agreed that alerting staff or the Order was a bad choice until they had freed Luna, just in case Nott or his accomplices had a way of finding out. With time running short, they made a rough plan of action and then left.
Unfortunately, there were nearly four times the number of Death Eaters they had expected to be waiting in ambush. To be fair, they had gotten her back and taken out a good portion of the ambushers, but ultimately it was eleven students versus nearly forty Death Eaters, including the entirety of Voldemort's inner circle—what was left of it, anyway, as his fight with the dark wizard had turned several of them to meat chunks when spells were redirected. Reducing the enemy numbers as much as they did—thirteen, including Lucius, much to Draco's satisfaction—was a great accomplishment.
But now they were trapped in a large room with only a giant arch that was almost blinding to his magical senses, and the remaining Death Eaters blocking the only door. He knew upon springing the trap and seeing the numbers and combatants present that the chances of escape were thin—the lower rank Death Eaters might be incompetent idiots, but the thirteen inner circle members were genuine threats, and he could only reliably fight three at once without using spells that risked friendly fire. Loath as he was to admit it, and despite all their training over the years, only Neville, Hermione, and Luna had any real chance of beating one of Voldemort's trusted. The others could only stall at best without special circumstances.
They had made it this far thanks to the general incompetence of the lower-rank Death Eaters. First, they were overconfident, allowing him and Neville each to send Bone-Breaker hexes at the heads of the two holding Luna's bound arms. Second, they were in the way of the inner circle, granting his friends precious time to start retreating and setting traps while he shielded against the few spells headed their way.
They made a hasty exit from the Hall of Prophecies while employing guerrilla tactics such as razor wire spells between shelves at ankle height, ice floors leading to spikes to take advantage of the Death Eaters' initial reluctance to Apparate and set off one of the intruder alarms, and one of Harry's personal favorites: proximity-detonated explosion curses on several shelves to thin the number of pursuers.
They had managed to successfully evade the Death Eaters for almost fifteen minutes, until one of the doors they went through led them to their current predicament. The two most damning issues at the moment were: the blindingly bright magic of the arch, which acted like a bonfire behind a firefly in that its magic blanketed out the attackers' magic to his senses, cutting his combat efficiency massively; and that the room was wide open, providing no substantial cover for spellfire.
Seeing they had no other choice, the Defense League members all squared their shoulders and engaged. The still-large disparity in numbers meant they were being pushed back and had to focus on defense. Seeing the attackers fanning out some, but not trying to circle, he called for an altered phalanx formation to buy time and save mana, which worked for a few minutes. Then, the Lestranges eventually wised up and started directing several Death Eaters to flank their sides as well as attack the ceiling to drop large chunks of stone on them, forcing the group to switch to testudo and basically trapping them. The number of shields required meant not enough of them could attack to take out members of the opposition. The Death Eaters had enough numbers to have one half shield while another attacked, and still have more attackers than his group had total, leaving the group stuck in full defense mode and rapidly bleeding mana.
This continued for nearly ten minutes, leaving most of the DL on empty. He was starting to contemplate leaving the defense and praying to Merlin that the pressure of the situation would allow him to control his firestorm spell enough to not potentially kill his friends, when the Order finally arrived, blindsiding the Death Eaters who hadn't let up their bombardment at all. This finally allowed the group a quick breather before they all jumped back into the fray, eager to finally be on the offensive.
A couple of minutes into the renewed fight the situation changed. Sirius, after an early success helping Moody put down Greyback, got cocky while fighting Bellatrix and almost caught a stunner to the chest that would have knocked him through the veil. Harry hit him in the side with a mild banisher, quickly spun, and fired off an overcharged Severing Curse. His senses finally having gotten somewhat used to the arch's presence and altogether done with this night, he was a bit more vicious than he usually was, lacing the spell with a nerve-shredder aura—a less potent and wider-effect version of the Cruciatus curse—hoping that even if she dodged, she would be rendered temporarily immobile by the pain and allow a follow-up strike to land. Bellatrix, having blocked several of his spells earlier, threw up a shield and prepared to return fire but had severely underestimated the spell's power, to disastrous effect.
The curse blasted through Bellatrix's shield and quite literally disarmed her.
This had the side effect of drawing out the previously concealed Voldemort, halting the fighting briefly as he made his grand, dramatic entrance, appearing in a large explosion of black smoke and defending his favorite minion from the follow-up attack Harry had sent her way. Harry was about to resume firing spells the moment it looked like the bastard would start monologuing, but Dumbledore chose that same moment to arrive with Fawkes before engaging in their form of banter. Dumbledore spoke condescendingly down to "Tom," treating him like a misbehaving child, and Voldemort responded with acid-laced words of ridicule. Then, without warning, the two titans of magic were volleying spells back and forth, and everyone took that as a cue and the battle began again.
In the chaos of all the fighting, two things went unnoticed. First, from her position on the ground, Bellatrix had managed to recover her wand with her remaining arm. Second, Peter Pettigrew slipped into the room while disillusioned. After surveying the fighting for a bit, the rat spotted an opportunity to distract the Order and gain favor with the Dark Lord. Without hesitation, Pettigrew seized it. Conjuring a steel stiletto, he banished it into Luna's back as she was fighting off three other Death Eaters. Seeing that he had succeeded, he took a moment to feel pride in his accomplishment, thinking about how pleased his master would be. Unfortunately, that would be his last thought before meeting oblivion.
A couple of seconds earlier, Harry had heard Hannah scream. Turning to defend her, thinking she had been hit by a spell, he was met by the sight of Luna, his precious Luna... lying motionless on the floor, the tip of a stiletto sticking out of her chest. His world stopped. His ears rang like a bomb had just gone off, and he tried to process what he was seeing. Out of the corner of his eye, he saw Pettigrew with his wand still raised in her direction and a pleased, excited look on his face. The moment his brain connected the dots, his magic lashed out without conscious thought... and pulped him. No fanfare, no warning, no dramatic flash of light; one moment he was standing there, and the next his blood was everywhere. His body looked like an empty plastic bottle that had all the air sucked out of it.
Stunned, everyone froze momentarily. Everyone, that is, except Bellatrix. Using the chance, she raised her wand in her remaining hand, took aim at the turned back in front of her, and stunned Dumbledore before he could regain his bearings. Voldemort, seeing his biggest opposition down for the count, took this as a chance to speak.
"There it is! That ruthlessness I knew you possessed! It's a shame it took your little girlfriend getting killed for it to come out, but that's what happens when you oppose me. Others die, and you're left with the shame of knowing it's your fault. If you had just submitted to me, they would still be alive. You've lost, Potter; Dumbledore is finished, and no one is left to save you. But let it never be said that I am not a benevolent leader. I give you one last chance here and now. Submit to me and I will let your friends live. In a few years, who knows, I might even be able to bring your lover back. With the two of us working side by side all the secrets of magic will be at our fingertips."
Harry just stood there for a moment, head down and eyes shadowed, before slowly nodding—though none could be sure if it was to Voldemort's words or to himself—and stepping forward under the stupefied gazes of all present. As he climbed the dais to stand in front of Voldemort, the Dark Lord smiled cruelly, an excited gleam in his eyes.
"A wise choice, Potter, now kneel."
Following the order, he slowly started to lower himself to one knee, but just before it could touch the ground, Harry looked up to meet red eyes, a smirk on his lips before speaking.
"See you in hell."
He then lunged forward, tackling Voldemort through the Veil.