Never make Princess Luna angry, it's bad for your mortal body, your immortal soul, and your mind.
Star Swirl the Bearded, 398 After Harmony, shortly after accidentally insinuating Luna's flank was fat, and losing most of his fur in the resulting inferno.
Queen Luna, after having been humiliated by having to rely on her sisters centurions- whom were normally little more then window dressing for the palace with few exceptions- wasn't angry.
She was enraged.
Her second, Mezza Luna, had some explaining to do. Luna marched towards her office with the pace of a mare on a mission. She had some explaining to do, that was for sure. How in her own name did she allow one of her sections to get away from her like that? Her failure looked poorly on Luna, and Luna wasn't the sort of pony to calmly and collectively summon her, explain the situation, and possibly discipline her.
She was the sort of pony that just bucked a door off it's hinges, which now lay at the feet of Mezza Luna's desk.
"Just what the hell is going on around here!" Luna yelled, standing in the doorway while her second responded with what was natural- utter shock.
"I... uh... your highness?" She asked, trying to figure out what was happening.
"You! You idiot! I just had to go to Manehatten to put down a section of the night guard. A section of my own night guard. A section that reports to you!" Luna shouted, the last loud word enough to shatter the window to the Canterlot Mountain behind Mezza Luna, and topple her backwards off her chair.
"I... uh.. I can explain, Archer was acting on his own!" Mezza Luna pleaded, pulling herself up with her desk.
Luna strode forward, her eyes glowing white with anger.
"Oh please, do you take me for a fool? One of his underlings mentioned you by name, and you would have had to know about the dozens of night guards working for him, along with all the money that his laboratory must have cost," Luna said, lifting the desk and tossing it against the wall with enough force that it shattered, exploding into pieces and littering the room with debris.
Which left Mezza Luna cowering before her.
"You're either incompetent, or treasonous, and I have no time for either. I'm sending you to Southrop-Grumman, you can babysit the factory there until I figure out just how far your scheming goes," Luna ordered.
"Y... your highness..." Mezza Luna stammered, as a trio of heavily armoured (and armed) night guards formed up inside the doorway.
"I could pronounce my sentence now, if you wish. The evidence against you is enough to warrant it," Luna threatened.
"Y... your highness, I have been nothing but loyal to you!" Mezza Luna pleaded.
"If this is what loyalty means to you, then I want none of it. Don't push me Mezza Luna, that I'm allowing you to even continue to exist is something I might reverse," Luna growled.
"I..." Mezza Luna trailed off, and glanced behind Luna to the trio of night guards.
They merely glared back. There was no hope for her there- they thought Mezza Luna had committed the greatest crime a night guard could- disloyalty to Luna.
"As you wish, your Highness," She said, coming to all four.
"Good. You are stripped of your rank, your treasury access, and you will not be able to travel from Southrop-Grumman. It will remain your prison until I decide what to do with you," Luna commanded.
She turned her back on her second, and gestured to the other guards.
"Go with her. Drop her off at the train station and return, she is permitted to bring nothing, not even her armour. You outrank her now," She said, and strode off between them as they came forward to take their prisoner.
"If I find any proof you had a direct hoof in what's been going on, I will see to it justice is served. Treason is a capital offense," Luna said.
"You've been a great fool Mezza Luna- you had it all. Why would you do this?" Luna asked, turning back towards her behind them.
"Because you wouldn't," Mezza Luna said.
Luna sighed. "You really are a fool. If I hear of you so much as sneezing in Southrop-Grumman, I will have you arrested. Is that clear?" Luna said.
"Yes, your highness," Mezza Luna breathed through gritted teeth.
"Good. Take her away,' Luna ordered, and approached the ruins of her seconds desk as the other guards pulled her out of the room.
Investigating her was going to take time. Luna would love nothing more then to simply hang her for what she's done, but there wasn't enough proof, yet. Execution was a critical tool of the state that Luna had turned to time to time, but only if the proof of capital crimes was beyond a reasonable doubt. All she knew at the moment was that Archer's section was in contact with her- but there was no evidence that she played a direct role.
Allowing it to happen at all was enough to sack her though, and it allowed Luna to release her pent up anger. She was able to think clearly now, having yelled a lot and smashed some stuff. Southrop-Grumman was in the middle of nowhere, and the only thing of note there was a factory and a small testing facility. Surely Mezza Luna could do no harm there. It might be more wise to arrest her, but that would inevitably become public- and any of her accomplices would surely go underground. This would take finesse, keeping her on a short leash was the best idea at the time.
Luna sighed, and stepped over the shattered desk to look out the shattered window to the mountain city. She had freed the bat ponies a little over a thousand years ago from the demented unicorn known as Sombra, and they had worshiped her for it. A thousand years without her had apparently changed them, and they were no longer the totally loyal agents of justice they had once been. Now they were their own people, with their own culture and society. The Night Guard had morphed into just another government agency, and like any government agency it looked out for it's own interests. Luna would have to fix this, starting by cutting out the cancer that Mezza Luna and Archer had spread.
She would cut it out with prejudice, but for now she had the war to focus on.
Luna yawned. She had been awake for nearly a full day at this point, and a rather eventful day at that. The world could wait for tomorrow, she knew, and left the wreckage of Mezza Luna's office behind her. She would sleep, and this time she hoped there would be no complications. Celestia could take care of the realm today, the lines were stable and Archer remained a threat, but at the moment there wasn't much to go on.
Sleep now, fight tomorrow, that's the ticket.
A short time later Mezza Luna boarded the train, the trio of guards at her side, and went straight back to scheming. Queen Luna had no idea she had just sent the lion into her den- Southrop-Grumman, also known as Location X. She was hurt, but she wasn't out yet. She had a plan.
She always had a plan.