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"A Welcome Back to the Home He Left Behind"
As shocked as people in Kings Landing were to see Rhaegar and his party returned, nothing shocked him more than to see Kings Landing so changed. Everything around him, though standing, looked tattered, frayed, and aged. Rhaegar felt no different. Still, he knew it was his duty, as king, to set things right. A small cry from behind him rang out and he turned to see his Jon's nurse try to hush the dark-haired babe in her hands. Rhaegar let out a small smile; yes, his small party, including the remains of his loyal Kingsguard, Sers Arthur, Gerold Hightower, and Oswell Whent, returned home. What was broken would be made whole again.
His thoughts turned back to the raven he received shortly after his victory over Robert at the Trident; "dark wings, dark words" indeed. The note from his wife began, "My Lord Husband", not "My Dearest Rhaegar"; then again, it hadn't been "My Dearest Rhaegar" since Harrenhal. Though he understood it, her formality pained him. Just then, Jon let out another cry; aye, he understood. Something else he needed to fix.
It had been the rest of the brief note that shocked him: "The King is dead. Your father often said fire cannot burn a dragon. Your father had been no dragon. Long live the King. If it pleases you my lord, return to Kings Landing at your earliest convenience. Now that you are victorious the city needs your presence. Your lady wife and Queen, Elia of House Targaryen".
His father was dead, he was king, and the usually gentle Elia could not find it in her to be kind about Aerys' passing. He hadn't wanted to imagine what transpired between Elia and Aerys for such a thing to happen. He had been far too distracted with making peace with the remaining factions lead by Lord Stark and Lord Arryn to try and understand what the rest of the note meant until Maester Pycelle met the returning party at the gates of the Red Keep.
The old man, like the rest of Kings Landing, looked tired. The maester was relived to see him. His voice was kind, but, filled with pity. The maester explained that the Queen, the children, and Ser Jaime were in the throne room. As the party walked towards the throne room Maester Pycelle relayed the entire sorry tale to the silent and horrified group.
He explained, though it was not surprising, that the king had been obsessively secretive, the days leading up to his death. Since the war began, many within the Red Keep had been subjected to the Kings unpredictable behavior and rage; as such, everyone took to avoiding the king unless summoned. The day he died, the King forbade all, even Ser Jaime Lannister, from entering his chambers. The king had been snappish and volatile for some time; no one voiced any objections.
That night the King had not made an appearance at the evening meal. The maester explained the former Princess, now Queen, and Ser Jaime came to retrieve him so that they, together, could perhaps convince the King to eat. When they reached outside the locked chambers anguished cries were heard and they smelled the oddest stench. Ser Jaime and a few others were forced to break down the door. The stench was of the Kings burning flesh and the King himself was engulfed in the strangest fire. The maester explained they put the fire out, but the king had been too far burned. The king died next day.
Standing outside the throne room after hearing this, Rhaegar couldn't find his words. His father had truly been mad. Horror, etched into every face around him mirrored how he felt.