Ursa- revenge, or a mother’s rage
The avatar spared the fire lord.
A small part of Ursa’s spirit commends Aang for his mercy and compassion, traits she once held herself but no longer had the luxury of.
But he never had to live under his thumb.
Never had to feel the sting of his backhand across her cheeks and his white hot flame against her skin.
Never had to go to court with a bloody lip and burns on her wrist.
Never had to hear the whispers hidden behind silk fans of the dishonor she must have wrought upon her husband to get him to react that way.
Never had to watch him abuse and neglect her sweet little son.
Never had to watch him isolate and groom her strong willed daughter and her blue flame into his weapon of war.
When she died escaping the palace after killing Azulon and saving her son, her only recompense was that perhaps she would find peace in the spirit world.
But it never came.
The problems she had been powerless to stop in her life only grew in her death.
Her son, her beautiful baby boy spoke up at a meeting in the war room in defense of his people and that bastard burned half of his face off, so much worse than he ever burned her, and sent him, a child of thirteen off on a fool's errand to capture the avatar so his honor could be restored.
Her daughter, whom she often quarrelled with but loved as much as Ozai would allow with his iron tight grip on her, was groomed and turned into something she could barely recognize as the scars that she was unaware she was leaving on her grew into chasms in her mind that only her father’s favor could ever hope to fill. She saw her daughter grow cruel and unstable, pushing everyone away when that bastard took all he needed and left her and lashing out at her when she manifested in her mirror.
Years of watching how that evil man hurt her beautiful children and turning them against each other hardened Ursa’s soft heart.
She wanted revenge, to inflict every little bit of pain he had onto her and her children back on him, to savor every scream and relish the fear in his eyes.
But the time was not right yet.
It was the avatar’s destiny to bring her husband to justice. And besides, if she killed him now with their children young and far from home, the already tumultuous political climate could turn against them, and even with a mother’s rose tinted view, she knew they both were far from stable enough to rule.
So she bided her time, subtly influencing Zuko to turn against his father and see a better path, and not so subtly appearing to Azula, and saw first hand the horrific way he had molded her mind combined with the scars from her mistakes.
Finally her son rose up against his father and joined the avatar, eventually deposing the wretch and taking the throne to build a better future. Her daughter was free from his influence and could now start to heal with her brother's support, though it was not going to be an easy road ahead.
Ozai was weak now, robbed of his fire and brought low, but perhaps not low enough.
She thinks it’s high time to pay him a visit.
The torches illuminating the prison flicker and dim as she manifests in the middle of his cell
She looks different than she appeared to her daughter. There she looked no different than she would have sitting by her favorite tree in the courtyard, feeding the turtle ducks.
But now, in front of the man who tormented her through both life and death, she appeared like she did when she died: in tattered silk robes and rumpled hair, an appearance he would have belittled her for keeping had she still been on the mortal plane. Her skin is as pale as a sheet, with bags and lines eerily visible in the low firelight. But perhaps the most horrific thing about her is the gash still open going across her neck, the red of her blood seeping into the golden collar of her gown.
A cruel smile graces her face at the look of terror that plays across his once controlled countenance.
“Ursa…” his voice shakes with fear as spits out her name with his usual contempt.
He changes his tune in an instant though, attempting to gain the upper hand again with his dominating presence that he no longer possesses.
“Leave Ursa. Go back to whatever hell you came from, you unlovable wretched girl”
Her face is deceptively serene at this, as pale chapped lips turn upwards slightly.
“Oh no, my dearest, I’ve come to settle a score”
Suddenly he’s surrounded by flames, just like he was when he was leading the world to ruin as the fire lord on his throne. He screams, and she smiles wider. Despite the chilling grin, tears as big as pearls fall from her empty eyes.
She yells in a terrifying fervor as the salt of her tears mixes with the blood of her wound but she can’t feel the sting, too caught up in her bloody justice. He can feel the warm blood trickling from his ear from her screaming.
She’s bearing down on him, nails like knives cutting into the skin under his jaw like he used to do to her so many times years ago as her fists and her palms beat his face into a pulp, exacting her payment in blood.
“This is for my son you bastard” she unfurls her fist and flames spring forth. Ursa was never a bender, but she seems to have better control over fire than he ever had. Without a second thought she presses her flaming palm to his eye, burning away layers of flesh as his screams echo through the cell. When she pulls away, the tissue of his face is burnt away and she smirks in satisfaction at her vengeance.
But she wasn’t finished yet.
She still had one more person to avenge, and since she had neither the time nor the skill to replicate what he had done to her daughter, he would simply have to pay with his life.
With a snap of her fingers, the room grew unbearably hot as flames surrounding them took on the sapphire tint that he coveted so much he broke her Azula. Her grip on his throat tightened till her nails broke skin and his vision blurred.
Invisible chains came to bind his arms and legs as the blazing fire closed in on them.
“I will leave you now, as a caution to the cruelest of men” was her parting shot.
The force of his terror seems to shake the world when she finally releases him from her hold, as she walks slowly away, leaving him to be consumed.
Her blood stained dress catches on fire, but she walks through it unaffected, until she vanishes into thin air.
Somehow, the sound of screaming and the smell of burnt flesh don’t rouse the guards, it’s as if they’ve been put into a trance. They don’t know what happened until they go to feed him the next day and find nothing but a blacked skeleton lying in the middle of a cell. How he died is a mystery to the mortal world, but the spirits know the truth.
The avatar might have spared the fire lord, but the spirit of the woman he hurt for far to long didn’t.