Use the cover of night and take Prism to study Fallen movements.
"That ambush at the Forgotten shore was no coincidence." Ghost spoke to the two hunters. "It's obvious something is happening near Rasputins core. You two will need to investigate the Rocketyard. There's been reports of a Fallen captain who has a key to the AI core here."
As Mercer piloted the ship, Prism sat in the back and shuffled his hooves nervously. He glanced a little at the Hunter, wondering what was going through his mind. The Pegasus went back to minding his business
"Don't give me a look." Mercer had said sternly
"I wasn't giv-"
"I know you were giving me a look." Mercer told him.
Prism sighed, showing signs of getting frustrated. "Look, I'm sorry. Are you really making me do this?" He asked.
"You saw me. I had to make sure you wouldn't tell them while I was gone." Mercer said to the stallion.
"Hey man, I was going to the bathroom. It's not my fault that when I see you walking out your room and loading a pulse rifle that I get suspicious."
"And now you're here with me." Mercer told him. "I'm glad we could come to an agreement."
"Agreement!?" Prism threw his hooves up in frustration.
"Relax, this will only be for a moment." Mercer said. "Ghost, we there?"
"Yes we are." The little floating pylon told them. "Bring us in, Guardian."
Mercer dove the ship into the planets atmosphere, Prism yelling at the g-force he was feeling in the ship hull.
It was there again, in his dreams. The arrow of purple light that pierced his mind from time to time.
Why must it appear now? Every time it does, it seems to tell Mercer there's something he needs to do. He saw it the night before he agreed to go to the Black Garden. It appeared after the Vault of Glass was open, prompting him to go in with a fire team.
It was a blessing and a curse to the Hunter. But he knew it was a way of reminding him of goals for humanity.
What would she be doing if she was there.... he wondered. Wasn't there something about a key?
Yes.... to the AI core. Sounds like something she would be into.
Getting out of bed, Mercer went over and examined his weapons. He glanced above his desk and saw the mounted, rusted handcannon. A solo job would require more than a Handcannon. He decided to take his Coiled Hiss 1919, his pulse rifle that he saved for certain missions.
Walking out of his room with the weapon in hand, Mercer closed the door and was surprised with Prism running into him.
"Oh hey..." The Pegasus said. ''What'cha up to?" He asked.
"Come on." Mercer told the pony. "Lets go."
For some reason, Prism said nothing else and agreed to follow the hunter.
The two landed onto the Earth's surface just as snow began to fall. Prism looked up to see only a small amount of clouds in the sky. That left enough space to see the bright stars that lit the Divide.
"You guys don't have someone who takes care of the clouds do you?" Prism asked.
"No... do you?" Mercer asked as he was checking his weapons.
"Yeah..." Prism said, still in awe over the scenery. "Pegasi can stand on clouds... so we can make it rain. My mom was a weather pony."
"Really now... I'd love to hear about." Mercer's tone dropped. "But right now, we need to move. It's luck if they wake up and find out we're gone."
"Right... so where to?" Prism asked.
"Not to far. It's a quick sparrow ride to where our target is." Mercer turned back to his ally. "How fast can you fly?"
Prism flared his wings, sparking them a little with arc energy as a sly and confident grin appeared under his helmet. "Wanna see?"
"No." Mercer said flatly. "You'll need to follow me, unless you've been here already. You won't know the way."
Prisms wings fell to the ground. "Way to kill a dudes excitement."
"Listen, we're in a good spot." Mercer said, looking around. Aside from a few buildings, the landscape was near empty. "This place has been considered good luck ever since a Warlock shot their way out of here."
"Really...?" Prism asked. "That's considered good luck to you guys."
"Well considering the odds they and their ghost were up against, I'd say yes." Mercer told the Pegasus as his Sparrow was formed. "You stay behind me and follow." He commanded.
"You got it boss." Prism responded. "Lead the way." He said in forced enthusiasm.
"Alright, lets make it quick." The Hunter said before speeding off, Prism following him.
Opening the door, the Warlock sighed upon seeing it empty. Fearing the worst, she turned and tiptoed through the hall and down to the where she was told they stayed at. Opening the door, she peeked inside to see the ponies sleeping in their bed.
Sighing relief, she closed the door. It opened again as she counted six. That was good right?
No, there were Seven!
Closing the door once more, she sighed and walked back to her quarters. She couldn't leave, and so help Mercer if he came back alone.
Mercer saw the target, yet he wish he could pick him off from the distance he hid. Sadly, it would have been easy for the Fallen patrol to leave the moment he picked one off. He didn't even know which one had the key.
"So, which one are we supposed to get?" Prism asked loudly. Mercer darted his hand over to ponies mouth and held it shut.
"Quiet! We can't let them see us." Mercer whispered to Prism. The two watched from the shadows.
Within the Rocketyards, the two watched an entrance to old Fallen Hideout that belonged to the House of Kings. The pair of Guardians had been waiting for a perfect moment to strike.
"We need to hurry up. They'll know we're gone soon if they haven't found out already." Prism told him.
"I know, just give me some time." Mercer responded.
"We don't have time." Prism replied. "We have to hurry up and get back to the Tower."
"Alright, just calm down." Mercer said. "Okay... we're going to have to charge in there and wipe them out as quickly as we can."
"Will that work?" The Pegasus asked, showing signs of getting nervous.
"Yes, don't you want to brag to your girlfriend about wiping out a group of fallen." Mercer told him.
"I said she wasn't my girlfriend." Prism explained. "So we're just gonna have to charge in. You have me back?"
"Of course." Mercer said as he cocked a shotgun. "We just need to go-"
The two watched as a Titan ran into the entrance of the Kings watch and began to open fire at the Fallen.
"NOW!" Mercer yelled as he ran at the Fallen, Prism following behind him with his wings readied.
Prism leaped over and flapped his wings to do a flip and slashed down the back of a Fallen dreg. Mercer slid underneath the Pony and kicked the Dreg as it was burning away. He fired a shotgun shell into the face of a Vandal before turning to see the Titan punching a captain to death. Suddenly, another Captain jumped on top of her and pinned her on her back. She looked over to Mercer as he slid his shotgun over to her, which she took to bash the Fallen in the face before shooting her.
Prism looked over to see a Captain trying to sneak away. The pony charged at him and tackled him to the ground. The Titan ran over and stomped on the Fallen's head until it's soul was ripped from his head. Mercer ran over and saw a kind of device on it's chest. He grabbed it and examined it.
"Just what I was looking for." He said. The hunter turned to his fellow Guardian. "Thanks for the help."
"Didn't know you even needed it." A female voice spoke. Prism perked up at the sound of her voice. "But I guess we'll be going to Rasputins core then?"
"Yeah, get a fireteam ready. We'll need a lot of help." Mercer told her.
"You got it, boss." She said, before turning away.
As she walked off, Prism thought she sounded a lot like Whirlwind. For some reason, he felt his face heat up.
"Come on, we got to get back." Mercer said as he pulled out his Ghost and returned the two to orbit.
The two arrived back to the tower. Only a few Guardians were awake at this hour. The two quickly made their way down the stairs to the living quarters.
"Okay, hurry back and if anyone asks you had to use the bathroom." Mercer told Prism.
"Oh, for two hours?" A voice asked. The two froze in their tracks as they turned to the source.
Ikora stood n the darkened hall, smiling at them. "I'll be honest, I was gonna shoot Mercer if he came back alone."
"I wouldn't blame you." He responded. "But I'm guessing you'll let this slide right?"
"Well.... as much as you deserve scolding for taking a Tower guest on a late night mission.... I used to do the same."
Prism let out a sigh of relief. "Get some sleep boys." She told them before leaving them.
"Alright... I'm going to bed. Goodnight Prism." Mercer said before walking off.
"Hey wait!" Prism called out, only to see his friend had disappeared. Sighing, Prism walked back to his room. He silently crept in and into his bed. Amazingly, no one woke up to find him gone. He was shocked. He really just snuck out of the tower and went on a quick mission.
"Wow..." he whispered in his bed. "I can't wait to tell everypony about this back home."
Laying his head on the pillow, he drifted off to sleep.
Prism and Whirlwind rested on a cloud overlooking Rainbow Falls, both tired after a long day of training. Stretching her wings, Whirlwind let them fall to her side, one happen to wrap around Prism.
"Man.... I can't wait to try out for the Equestrian games." She said.
"Same here." Prism said. "And if there's anypony who can make it, it's-"
"Let me guess," Whirlwind cut him off. "You."
"Actually..." Prism stammered for a moment. "I was gonna say both of us." He said, turning to her.
"Aw. Finally you realize how much better I am at flying then you." She replied.
"Yeah yeah." Prism said. "But I'd miss you to much when if I got picked and have to leave for the Crystal Empire without you."
"Oh hush." Whirlwind slugged his arm with her hoof before giggling and pulling him close. "Good thing I'm so great that we'd be going together." She said.
"Yeah...." Prism looked out into the distance, seeing a noticeable outline of a celestial body. "Good thing we'd leave together..."