Having grown up together and fought side by side for years, Rostam and Arundolyn did not waste time on pleasantries when they met. Instead, they shared an unspoken bond—a tacit fist bump—and immediately began teasing each other.
Arundolyn said bluntly, "I heard you charmed a noble lady yesterday, lured her to Cat's Tail Tavern, and got her drunk. You didn't do anything improper, did you?"
Rostam's face flushed with embarrassment. Even now, recalling the events of the day before felt like a dream. He had met Rosalyne in a daze, impulsively invited her to the tavern, and somehow confessed his feelings, and she had actually accepted. Even more absurdly, they had publicly pledged their love before the statue of Barbatos and even hired a bard to play them a song of freedom. It was like a dream.
But thinking of Rosalyne's gentleness, Rostam smiled. "I am the Deputy Grand Master of the Knights. Of course I wouldn't do anything improper. But you, Grand Master—it's time you thought about settling down yourself."
Arundolyn looked at Rostam's smug expression and was speechless.
He didn't want to say another word.
But then, his expression turned serious. "Enough joking. I have important news. Word from afar says Khaenri'ah is about to undergo a catastrophe—it may well be destroyed."
Rostam was startled. "Arundolyn, you can't be serious. Who could destroy Khaenri'ah? Could it be Liyue, Inazuma, Sumeru, Snezhnaya, Natlan, and Fontaine all attacking at once? Even that seems impossible—there's no reason for war."
As Deputy Grand Master, Rostam was well‑versed in the current affairs of Teyvat's nations. As far as he could see, there was no reason for war.
But Arundolyn gave a name that was unfamiliar to most ordinary people. "The Heavenly Principles. I'm not certain, but from what I've heard, it's likely the case."
For common folk, the Heavenly Principles were nothing more than a distant legend. But as the leaders of the Knights of Favonius, both Arundolyn and Rostam had never seen the Heavenly Principles, yet they believed they existed—and that they controlled the course of the continent in some way.
Hearing that name, Rostam's expression grew serious. "What do you plan to do?"
Arundolyn replied, "Without the Anemo Archon, we must act before anyone else. I will lead the Knights to Mondstadt's borders and fortify our defenses against whatever may come."
Rostam did not argue with his decision—he had been thinking the same. "Let me go," he said. "Mondstadt and the Knights need you here to lead."
But Arundolyn was firm. "Rostam, you know that although I am the Grand Master on paper, and you are my deputy, in practice it is you who does the work of the Grand Master, while I charge into battle like a deputy. Mondstadt needs you more than it needs me."
He was right. Since the founding of the Knights of Favonius, the Grand Master should have been handling administration and issuing orders, while the Deputy Grand Master took the field. But their personalities had reversed those roles—Rostam, the deputy, did the Grand Master's work, while Arundolyn, the Grand Master, fought on the front lines.
It was an unusual arrangement, born from their deep bond as brothers.
Arundolyn continued, "And you must not slack off. You're staying in Mondstadt, so you must protect it well. When I return, I don't want to see a wasteland."
Knowing he could not change Arundolyn's mind, Rostam sighed. "Don't worry. As long as I'm here, no one will harm Mondstadt. You be careful, too. I'll have the finest wine ready to celebrate your triumphant return."
He raised his hand. Arundolyn raised his, and they struck palms in a solemn vow. "It's a deal. I trust you to guard Mondstadt well."
In that moment, both Rostam and Arundolyn were ready to give their all for Mondstadt.
Just as Arundolyn was about to leave, he turned back. "By the way, I heard you've developed a new swordsmanship called Favonius Bladework and plan to teach it to the Knights?"
Rostam smiled confidently. "That's right. It may not be as sharp as your style, but it's simpler and easier for all knights to learn. If the entire Order masters it, we will become the most powerful army in all of Teyvat."
As brothers who had grown up together, Arundolyn knew Rostam would never lie. "Good. Teach it to the knights who remain. When I return victorious, the whole Order will learn your Favonius Bladework."
Rostam's face lit up. "That day won't be far off."
And so, after a brief reunion, the two leaders of the Knights of Favonius had to part once more.
That very afternoon, on Arundolyn's orders, the Knights assembled all their elite soldiers, gathered vast supplies, and equipped the finest horses and weapons. Amid the cheers of Mondstadt's citizens, they marched out of the city toward the designated border locations to build fortifications before the monsters arrived.
Now, standing atop Mondstadt's city walls, Rostam watched Arundolyn's departing figure and silently prayed to Barbatos for his protection. He asked the Anemo Archon to watch over his dearest brother.
At the same time, Arundolyn, leading the main Knights' force, also looked back at the receding city and offered his own prayer to Barbatos—that he would protect Mondstadt and keep Rostam safe.
...
Meanwhile, in a tavern in Mondstadt, a bard who had just earned ten thousand Mora from busking rushed in and slapped the coins on the counter. "Barkeep, a jug of your finest wine, to go!"
"Ah—ah—achoo!"
"Eh? What's this? Someone prayed to me yesterday, and now someone's praying again today? How troublesome. I'm busy—I have to busk for Mora and keep an eye on Khaenri'ah. I don't have time to grant wishes. Maybe it's time I visited Khaenri'ah and took care of that problem myself."
In fact, it was Barbatos himself who had passed the news of Khaenri'ah's coming destruction to Arundolyn. For once, he had actually done something useful.