This is a little story that I wrote based on all the history you learn from Maechan as you play the games. If it's a trifle inaccurate, well, blame it on fading memories.
Zanarkand glowed brightly in the glowing darkness. Yunalesca, one of the most powerful summoners in the city, stood on the balcony of her palatial home. Her long white hair trailed behind her in the gentle breeze. A gown of emerald silk clung to her graceful body as she watched in vain for the return of the soldiers.
The war with Bevelle was growing more and more dangerous. Yu Yevon was getting impatient with the younger summoners. They were falling too swiftly underneath the onslaught of the terrible machines, their aeons dying with them.
With the loss of Lenne, that most talented songstress-turned-summoner, Zanarkand was rapidly losing hope. Lord Zaon, Yunalesca's husband, walked into their bedroom. He went immediately to his wife's side. "My love, have you been called to the front?" he asked worriedly.
Yunalesca sighed and placed a hand on her gravid womb. "No," she said. "But with Lenne gone and Yu Yevon descending into madness, I fear that once our child is born, I will have to go."
Zaon pulled her close. He felt the life growing within his beautiful wife move in protest. He smiled. "She does not like to be squashed," he commented.
"No she doesn't," Yunalesca agreed. She put both her arms around her stomach. "Easy now, baby. Daddy didn't mean to squish you." The unborn infant settled down immediately.
"'Lesca, I have to return to the front," Zaon began.
"I know," Yunalesca replied. "You are a general in our army. Please be careful, my lord husband. I don't know what I'd do if I lost you." Zaon kissed her gently before walking out the door. Yunalesca curled up on the huge canopy bed and cried herself to sleep.
A few weeks later, Yunalesca was deep in her labor when Zaon returned. The doctors allowed him to remain in the room as his wife pushed with all her strength. Finally, with an agonized scream, a squirming, bloody baby was delivered into the doctor's hands. "It's a girl!" came the cry. Zaon kissed his exhausted wife on the forehead. The infant was cleaned up and placed on Yunalesca's newly deflated stomach.
"What are you going to name her?" someone asked.
"Lescana," Zaon replied immediately. "Her name is Lescana."
"Such a pretty name for such an extraordinarily beautiful little girl," another person commented. Lescana was indeed very lovely. She had her mother's pale hair and her father's dark blue eyes. She looked around her alertly, though she was only a few minutes old. Yunalesca took her and placed her at her breast. The baby knew what to do and began sucking away at the nipple.
The next day, Yunalesca and Zaon took their daughter home. When she fell asleep, Zaon sat beside his wife in their bed and spoke of the ongoing conflict. "Yu Yevon's madness is spreading faster than we can contain it," Zaon said worriedly. "He's been talking about a 'Final Summoning', calling down the wrath of the aeons on Bevelle. I think his daughter's death has rattled his wits."
"Yu Yevon has never been very stable," Yunalesca murmured tiredly. "Lenne's death is just his excuse to grab for more power."
"How long do you think it will be before they call you back to the front?" Zaon asked.
Yunalesca snuggled closer to her husband. "He said I could have a few months with Lescana before he called me back. I'm hoping for more, but I won't count on it."
"What are we going to do with her if we're both fighting in this damned war?" Zaon wanted to know.
"I've already spoken with Iva and Thorak," Yunalesca informed him. "They'll take her until we return."
"Good," Zaon said. He pulled his wife close and the two of them drifted comfortably off to sleep.
Three months later, her body returned to fighting trim by a great deal of effort, Yunalesca and Zaon faced the toughest decision of their lives. Iva, Yunalesca's younger sister, held out her arms. Zaon handed her the sleeping baby. "She's growing so fast," Yunalesca said tearfully. "I'll miss so much."
"We'll take good care of her, 'Lesca," Iva promised. She cuddled the baby and smiled. "She's a good baby."
"Yes she is," Yunalesca began. A messenger from the front burst into the room.
"Lord Zaon, Lady Yunalesca, it's Lord Yevon," the young man gasped. "He's gone insane! He has started his Final Summoning, and he's using one of his aeons instead of a human. Nothing can penetrate the shell he's cast over himself. Not even the machine weapons of the heretics in Bevelle!"
"What is that fool thinking?" Zaon demanded.
Yunalesca kissed her daughter's forehead. "Let's go," she said in a heavy voice. "If anyone can stop him, we can." Zaon and Yunalesca practically ran from the house.
By the end of the week, the damage was done. Yu Yevon's Final Summoning stopped Bevelle's onslaught. It then turned on Zanarkand. With Yu Yevon still trapped inside, the monstrous form, birthed in sin and pain, devastated everything around him. Yunalesca, Zaon, and the rest of the ragged remnants of the army slipped back into Zanarkand.
Yunalesca stopped by her sister's house to see her daughter. Lescana squealed with delight as her mother held her close. "It's useless Iva," she said with a heavy heart. "Nothing can stop him. He's become a living monster. His only goal is the utter and total destruction of everything."
"Can't you do something like what he did?" Iva asked.
"A Final Summoning must be a shared responsibility," Yunalesca informed her. "It is supposed to be born of a bond of love and trust between two people." Her voice trailed off. She suddenly burst into tears. "Iva, promise me something?"
"Of course," Iva said.
"Promise me you'll take Lescana and leave Zanarkand," Yunalesca sobbed. "Take her and go far away from here."
"'Lesca, what's wrong?" Iva asked, truly concerned.
"I know how to stop Yevon," Yunalesca replied, stifling her sobs as her baby girl looked up tearfully at her mother. She kissed the tiny face as many times as she could. "I won't be coming back, and neither will Zaon. At least, we won't be coming back if he agrees with what I have planned."
"You'll use each other for the Final Summoning," Iva whispered.
Yunalesca nodded. "Tell Lescana, when she's older, that her mama and daddy loved her so much that they died to protect her," she said. "Tell her that we did what we could so she would be able to grow up strong and happy and healthy."
"I will," Iva said. Thorak came up behind his wife. "We will. I promise, 'Lesca."
"Thank you," Yunalesca said. She held her baby for as long as she could. Finally she handed her back to her sister and fled the house, sobbing the entire way.
Zaon met his wife at the door of their home. "'Lesca, what is it?" he asked.
"Zaon, do you love me?" Yunalesca asked.
"You know I do," he replied, a little confused.
"Do you love Lescana enough to die for her?" Yunalesca persisted.
"My love, what are you – ?" His face paled. "The Final Summoning?"
"It's the only way," Yunalesca choked.
"But you'll die too," Zaon replied.
"Iva has Lescana," Yunalesca told him. "I asked her to take our baby someplace far from here, where they'll be safe from the summoning."
"When do you want to do this?" Zaon asked.
"Tomorrow morning," Yunalesca said. She wiped her tears away with the back of one hand. "I won't let him destroy this world."
"Neither will I," Zaon replied. "Yunalesca, I knew there would come a day when, as both your guardian and your husband, I would have to make the choice between protecting you and living and protecting you and dying. So long as I'm with you in the end, I will leave this world happy."
"As will I, my lord," Yunalesca said with a faint smile. "As will I."
The people of Zanarkand watched in horror as the monstrous body of their former savior approached, intent on destruction. Standing alone before the onslaught was the slender, graceful Lady Yunalesca and her mighty husband Lord Zaon. They stood on the steps of the temple, the only place left that could handle the power about to be unleashed. Only a single family, intent on escape, ignored the incipient clash.
Zaon kissed Yunalesca one last time before entering the temple. Yunalesca turned to the people of Zanarkand. "If this works, both Zaon and I will die," she said in a clear, calm voice. Only her eyes showed the bleak sorrow filling her heart. "But this sin will be undone and calm will return to the land." She followed Zaon into the temple.
No one knew what happened inside. But as Yu Yevon approached his former home, the temple exploded outward and a mighty aeon bearing some resemblance to Zaon roared up out of the wreckage. He fought valiantly and pushed the evil creature back. As Yu Yevon's creation finally slunk away in defeat, the aeon flickered and vanished in a flurry of pyreflies.
A few people went inside the temple to see if there was anything left of their two heroes. Zaon's body was encased in an elaborate prison, sealed over with crystal. Yunalesca lay on top of it, her lifeless form reaching out even in death to her beloved husband.
Bevelle knew of their deaths almost as soon as they knew of Yu Yevon's defeat. They rallied their forces and marched on the defenseless city. The remaining summoners gathered in what was now the tomb of their greatest heroes. "We can't hold out against their machines," one woman said wearily.
"But what else can we do? We can't just give up and let them destroy us," came the angry reply.
"There is another way." Terikan, Zaon's cousin, stood up. "My cousin and his wife bought us some freedom from Yu Yevon's sins. What if we were to call him back?" There were some muttered oaths and a great deal of shock. "Hear me out. I mean a full summoning, calling him back to deal with Bevelle but putting limits on what he can do. That's what we as summoners do, isn't it? Call upon the fayth to bring out the aeons to help us fight? We use the hymn and call him."
"How?" a new voice demanded. "How can we control him when it took two lives just to drive him off?"
"By using the people of Zanarkand," Terikan replied. "We bind them, as fayths, and use their power to fuel our summoning. Only we do not keep those that don't wish to become part of this Great Summoning."
"Are we to undo what your cousin and his wife sacrificed their lives for?" someone demanded. "They died to drive that monstrosity away."
"Don't worry," Terikan soothed. "With the Great Summoning, we'll be able to call him forth and get rid of him at the same time." Though there were still some doubters, it didn't take long for the group to agree with Terikan's plan.
Only a handful of people, with family outside the city, chose to leave. The rest remained. Mt. Gagazet resounded with the glory of the Hymn of the Fayth as the summoners began their work. Each and every soul still in Zanarkand was bound in crystal and stone. The summoners died, but Bevelle was stopped as Yu Yevon once more rose to defeat them. Then Terikan and his sister used the last of their powers to call once again on the Final Summoning. Zanarkand was destroyed as Yu Yevon's powerful creation faded away. Little did they know that in ten years' time, their efforts would prove to be in vain as the dreadful demon now called Sin rose again…