A/N: This is it. The *mighty battle.* Sorry again for crappy fighting exposition.
At first light, the boats are in the water. Every member of the Dawnguard except a small force left in the fort crosses the bay. The air is filled with a nervous excitement, and Gunmar must keep the wardogs from howling. Destra's eyes are closed, and she breathes purposefully. Serana shifts in her seat. As the castle draws nearer, Destra takes her hand, and Serana settles some. She is as prepared as she can be for the battle to come, but this does little to ease her conscience. Instead, she tries to focus on the cool air and the woman beside her.
The boats hit the sand. After they are hauled to shore, the soldiers break into three groups. One is led by Isran, another by Celann, and the last by Gunmar. Each group gets three hounds, and the last is left with Sorine, who stays behind to tend to any wounded. Destra and Serana's objective is to get to Harkon as quickly as possible. Isran doubts his lackeys will stop when he's dead, but it may make them lose some focus. Serana laughs at the thought. Half of Harkon's court would have killed him themselves by now if they thought they stood a chance.
The Dawnguard marches to the bridge that connects the main shore to the castle. As they approach, the gargoyles that line it burst to life. Isran's squad leads the way and jumps into action. The first two gargoyles go down with little effort, but the next manage to down a soldier. Isran growls and shatters the skull of one beast with his warhammer. His squad slays the other just as the first of the vampires emerge from the castle.
Three of the Dawnguard are slaughtered almost immediately. The rest of Isran's squad is so startled that a few turn to run. Isran shouts at them to not be cowards. He recites a spell from a scrap of parchment that Sorine crafted, and an aura of divine light surrounds him. He rushes the cluster of vampires, and their flesh begins to burn. Screeches fill the air. The Dawnguard takes heart in this, and they rush in to destroy the remaining vampires. The path to the gate is clear.
A vampire emerges from the shadows as Isran prepares to open the gate. He raises his axe and swings down at Isran's neck. Before it connects, an arrow sings through the air and lodges in the creature's eye. Isran whips around to see the corpse burn to ash. Destra stands a few yards back, Auriel's Bow shimmering in her grip. Isran nods his thanks, and she nods back. Celann helps Isran with the gate, and all squads rush in.
The battle is chaos. The close quarters of the courtroom make it difficult for both sides to avoid friendly fire. The Dawnguard must rely mostly on their melee weapons instead of their favored crossbows, allowing the vampires to get within biting distance. Even so, bolts and spells fly across the room, striking friend and foe alike. The Dawnguard huskies clash with the vampire deathhounds in a bloody brawl. Serana cannot tell which side has lost more fighters.
She and Destra manage to slip past the bulk of the frenzy, but the way to Harkon's sanctum is heavily guarded. A group of five fledglings led by a master barrels towards the women. Destra fires an arrow and fells a fledgling. The arrow explodes, and the flames disintegrate two more. Serana exchanges spells with the master until she catches him with an ice spike. The last vampire tries to sneak up on Serana while she is distracted. Destra runs her through.
They are about to advance on the sanctum when they hear the clinking of armour come from down the hall. Destra turns with a readied arrow. Isran runs toward them with Gunmar and a handful of others. He tells them they'll guard the door while they face Harkon. Destra nods and the group pushes on. A few more vampires stand in the way, but they stand no chance against the Dawnguard. Finally, they arrive at the doors. Destra looks to Serana. She takes a deep breath before nodding back. Together, they push open the doors and walk into the sanctum.
Harkon stands with his back to them at the end of the room. The hall itself is enormous, with twin balconies on either side and a raised altar of sorts where Harkon stands. On it is a fountain that cascades blood. Harkon dips his fingers into it and tastes. He does not turn when he addresses them.
"And here comes my lovely daughter now. And her pet, by my smell," he drones. He turns then, and his eyes are a different colour than Serana remembers.
"Father. End this now. Call off your men. We have the bow, and you don't have my blood. There is no way for you to fulfill this prophecy. It's over," Serana says. Harkon sneers and then tuts at her.
"My dear, you've brought both the bow and your blood to me now, don't you see? Give me the bow, and with but a few drops, I will show you what I've worked all of these centuries to provide our kind." He steps toward Serana, and Destra places herself between them.
"It won't happen, Harkon. Listen to your daughter. She's offering you your final chance," she says.
"Down, girl," Harkon growls, "or I'll slaughter you where you stand. I've already shown you mercy once, and yet here you are again." He raises a hand, and a red orb forms.
"You will not touch her." Serana growls and summons her own magic. Harkon chuckles.
"Listen to how you whine, Serana. I imagine your dog will howl." He releases his spell at Destra. Serana casts a ward over Destra before flinging an ice spike at her father. He effortlessly dodges it and grins.
"And so it begins," he says. A crimson mist engulfs his body. When it clears, he emerges as a vampire lord. Destra has seen this from only once before when she first met him. She admits that she finds it disarming. She raises Auriel's Bow anyway and knocks a sunhallowed arrow. Harkon moves quickly, and Serana must distract him if Destra is to land a hit. They sync their movements.
Serana begins with a bolt of lightning. Harkon vanishes in a cloud of bats and reappears across the room. Destra fires where she thinks he'll be and misses. He laughs at her and counters with a spell. It connects with her before Serana can do anything. She feels drained, as though she just climbed the Throat of the World, and falls to one knee. Harkon rushes her with his sword. Destra draws one of her own to parry the strike, but she is almost too weak to lift it from its scabbard. She tries to summon a shout, but the magic dies on her tongue. Out of options, Destra braces for the impact.
But the blow never lands. Serana stands in front of Destra, her dagger crossed with Harkon's sword. She grimaces as he tries to push past her blade, but she manages to hold her ground. With every ounce of willpower she possesses, Destra swings her sword and lands a slash on Harkon's bare leg. He grunts and falters back. Serana strikes out, but he dodges her blade. Harkon retreats in his bat cloud and reappears by the blood fountain.
A black aura surrounds him, and as he drinks from the fountain, the wound on his leg begins to close. Serana tries another lightning bolt, but Harkon's barrier absorbs it. Destra is able to stand again, and she once more draws Auriel's Bow. The sunhallowed arrow pierces the barrier and explodes in a ball of sunlight. Harkon is hurled against the wall, burns covering his skin. He shrieks so loudly Destra must cover her ears. Serana is not deterred. She is upon him in an instant, her dagger to his throat. They lock eyes.
"Death then, Serana? You would kill your own father? To save the pathetic beings that crawl like insects upon this land? To save that creature you're so fond of?" Harkon spits. He glares at Destra, who now has an arrow trained on him. She only draws back farther.
"My father died a long time ago. I don't know who you are, but I do know you need to be stopped," Serana says. "So no, this is not for them, or even for her. This is for me." She presses the dagger close enough to his skin to draw blood.
"Then do it. If you can."
Serana hesitates for only a moment, but it is long enough for Harkon to knock the dagger from her grasp. As she watches it skitter across the floor, Harkon knees her in the stomach and reaches for her throat. His claws sink into her neck and-
The arrow pierces Harkon's chest. His grip slackens as he looks to it and then back up at Destra.
"May your gods forsake you, dog. I would have-" Serana drives the arrow deeper. Harkon's skin burns completely until his body is nothing but ash.
"Goodbye," she whispers. She is breathing heavily, and Destra thinks she might cry. She does not. Serana stands, walks to Destra, and wraps her in her arms. Destra holds Serana closely and strokes her hair.
Isran and Gunmar burst through the doors, weapons raised. When they see the pile of ashes at the embracing women's feet, they know it is over. Serana releases Destra when she hears Isran approach. He looks at the ashes and then back to Serana before placing a hand on her shoulder. He gives a gentle squeeze, then turns and leaves the room with Gunmar. Serana and Destra hear the Dawnguard roar their victory throughout the castle.
Destra is fifty-six years old. She knows she won't live forever. The world is safe again, for now.
A/N: And that's it for the Dawnguard quest line. The dialogue in the Harkon battle might be a little hackneyed, but no more so than in-game. Onward to the last of the arcs!
