Wrought Iron Devil: Gate of Blades

Authenticity

"Here's the deal; We've mobilized what firepower we can around Nijo Castle. Everyone else is organized near Kyoto Station. The Hero Faction hasn't made their move yet, but there have been some unsettling mana disturbances." Azazel began in this emergency briefing with all parties involved.

"The ley lines?" Medea asked.

"Yep. They're being siphoned off. Whatever it is, it can't be good." He affirmed. "There's also the issue of that little parlor trick in Cao Cao's posse. Unless you can pinpoint the Dimension Lost user, we won't have any Servant support."

"What about Rule Breaker?" Issei asked the more obvious question.

"(F/n) could use it. And then he'd have to do it repeatedly as the Dimension Lost user redoes the whole thing. That's a race we can't risk learning the outcome of. And it'd be a waste of Command Seals if it weren't something we could handle." Azazel reasoned. "If Dimension Lost is used, we're on our own."

"To that end, the Sitri family will be at Nijo Castle as our offense. The Gremory family, who has two Masters, hangs back at Kyoto Station. We can't afford to lose Masters." The Fallen Angel Governor drew two vials from his pocket. "We've got Phenex Tears, but unfortunately that was all I could round up."

"I've got Avalon projections too." You added.

"Good. Raynare?"

"Yes Governor?" The Fallen Angel straightened up.

"I'm placing you with the Gremory family, specifically your person of interest. Put your honed skills to use."

"Yes sir."

"I will be supervising the battle from here. I can't go with you, so don't you dare die on me. This trip isn't over until everyone is back home. Protect Kyoto and yourselves! Got it?"

"Yes!"

Underworld, Gremory Territory:

"Is that the best you got Satan spawn?" Mordred sneered at the Old Satan devil that had been run through by Clarent. "I'm not even trying here!"

She promptly bisected him to free her blade, then charged at more Old Satan goons. The devil terrorists had managed to infiltrate the Gremory Estate, causing mass destruction in one district. As friendly forces were spread thin, it was Rias that was called in. She and her friends were more than capable of handling themselves. But the fact that they had the Knight of Rebellion on their side made it much easier. Once she was on offense anyway.

When the skirmish started, Rias and Akeno had their sigils up for defense. Gasper and Koneko were limited in the face of a magical attack barrage. The only suitable counter could have been the Dhampir using his abilities to flank, but he was too unnerved to focus properly this time never mind actual attack. It was then that Akeno noticed Mordred just standing between the shielding pair holding her weapon on her shoulder in casual attire looking a bit frustrated.

"Mordred, can't you attack them?" Rias had asked.

"I would if I could Rias! Hell my Magical Resistance would do wonders right now! But I'm staying with my lady like her boyfriend told me to!" She explained. Right, she took her role as knight pretty seriously. In this case, her job was to stay with Akeno per (F/n)'s orders. In this literal interpretation, she could not just leave Akeno's side. Fortunately, the priestess realized something to get around it.

"Mordred, one could infer (F/n) was telling you to protect me right?"

"Yeah?"

"What are you protecting me from?"

"Uhhhh, them I guess." Mordred shrugged in the direction of the Old Satans.

Akeno smiled mischievously. "And what's the best defense my brave knight?"