Gabriel took in the marvelous sight as they approached the gate.

The towering main building - shaped like the blade of a sword stuck up into the sky - was ringed by a curtain wall half a kilometer high. The structure seemed built around what looked to Gabriel like an orbital cannon. He could see a colossal barrel peeking out above the building. The tremendous THUMP he heard as the weapon discharged shortly after proved him right.

The massive doors swung open as they neared, turrets placed along the wall turned to face them. So many turrets, Gabriel thought. They crossed the entrance into a large field. Open areas were ringed by red lines around the grounds. A tough-looking obstacle course took up a fourth of the outdoor zone. From inside, the main building seemed to grow, accentuating its proportions as they neared the second set of doors.

They entered what looked to be a hotel lobby, complete with luggage carts and everything. Zero strolled up to the machine at the desk. “003 here for my usual room.” He sent his credentials via wrist-pad and pointed back at Gabriel with his thumb. “The kid’s new; he’s gonna need the whole spiel if you don’t mind. Get him a room too, he’s boarding here.”

The machine started calculating, and Zero walked closer to Gabriel. “I’ll be seeing you later, Gabriel. It was a pleasure to meet you. Enjoy your tour.”

Gabriel shook the Hero’s hand and nodded. “Thank you for stopping Lucian. You saved us in there.”

Zero waved it off as he started towards the elevator. “Just doing my job, kid. It’s you who had the guts to stand up to the guy on such uneven footing. Plus, I have a feeling you’ll be watching my back in the field soon enough. See you later.” He winked.

The elevator doors closed behind Zero’s small frame, and Gabriel turned to the receptionist, surprised to see him gone, replaced by an automated droid. The little robot was rectangular, its body tapering slightly from the bottom with a thick wheel at its base. It had a single lens on its “face” and two small silver arms with pincered hands. Must be the tour guide.

Sure enough, the Bot began its programmed introduction. “Welcome Gabriel to the Sentinel Headquarters - more commonly referred to as the spire.” It said in a pleasing yet monotone voice. “Before we begin, please select your experience; Please select Civilian or Sentinel.”

“Sentinel,” Gabriel whispered, scarcely able to believe he could refer to himself as such.

The Tour Bot beeped, then continued. “Very well, please leave your belongings on the counter and follow me. I assure you they will be kept safe and taken to your private room.”

It started rolling towards the door of the dormitory. “Please feel free to ask any questions you may have, Sentinel.”

Gabriel thought of what to ask, if anything when vibration in the floor chose his question for him. “Why is this building built around an orbital cannon?” He queried.

The machine responded almost immediately. “The orbital cannon is one of five left under the control of the Sentinels. These are the main weapons employed against the Blitz. The rounds from the gun are enough to force the aliens to change location when fired. We use it to force them away from targets they are striking from low orbit.

The machine's honesty pleased Gabriel, who had become used to secrets within secrets surrounding his every move. “Please continue with the tour.” He said when he noticed the robot had stopped as if waiting for another question.

The robot lead him out the door and onto the single circular track that ran the length of the wall. “Every structure in the Spire is made of reinforced heat-ablative polymer. The wall is 760 meters high and 200 meters thick at its base. It has been used to repel Blitz attacks more than once and has held every time.”

The robot’s metal arms gesticulated as a person would while talking. “Atop the walls sit exactly 2046 Plasma turrets, all fully automated and controlled by separate Virtual Intelligences or VI.”

Gabriel was familiar with VIs, having designed some himself. Gabriel appreciated the turrets in all their glory with his suit’s visual magnification. Each matte gray turret was enormous, easily twenty meters in length. A single blast from one would be enough to vaporize a six-story building.

Soon, they neared the first ring of flags. The area was an empty circle of grass. “This is our customary transport pad. Here is where arrivals usually land, it seems Zero elected to bring you through the main gate, for impact, no doubt.” The guide explained.

Gabriel had underestimated the robot. It wasn’t just following simple programming. It knew the entrance he’d come in from. It had also extrapolated what Zero’s intentions could have been from that fact. That meant it was likely AI.

The implications of true AI wandering freely within the confines of the Sentinel stronghold kept his mind busy until they neared the next ring. This one looked like a weapon testing range, craters, and singed grass were obvious clues.

“This is our live combat area. The zone is surrounded by an invisible reinforced wall, and the Sentinels used it for advanced combat testing - for generations before simulations became a better option.”

Gabriel started to daydream about the simulations that replaced physical combat training. Grateful. Before he noticed, he outpaced the robot. He saw it standing on the path behind him. “This is the Ring of Remembrance.” It said when he backtracked.

The Super looked out at this ring, not circled by flags but by flowers of every color. It was full of obelisks. Each one was made of white marble and covered in golden plaques. From where he stood, Gabriel could see that the plaques held the names of Supers who died in the line of duty.

The beauty he beheld was moving. He felt a tightening in his chest. How could the MechaBlitz have destroyed so much, so carelessly?

How long he stood there, he did not know, but his guide waited patiently at his side. Thinking he had lingered too long, Gabriel turned to catch up and bumped roughly into the robot.

As the mech fell - pinwheeling its arms to avoid losing balance - Gabriel reached out and caught one of them. Righting the robot, he said, “Sorry about that.”

The Bot turned towards him and was silent for a time, gazing at the Super through its unreadable lense. Gabriel was worried he had offended the machine when it said, “Thank you for the help, Gabriel, and the apology. No one has ever apologized to this unit.”

It went silent, then turned down the path. “We must continue with the tour, and I have other duties to attend...friend.” It said the word as if trying it on for size, but rolled onwards at a good pace.

Perplexed but hopeful that he indeed had made a new friend, Gabriel jogged after it.

The final ring was exactly what Gabriel first assumed, an obstacle course. The words didn’t seem to do it justice. Gabriel saw machines meant to do nothing but destroy or throw objects all around the zone. Lasers, meat grinders, and saws littered the area. An old decommissioned Battle Bot stood in the center, surrounded by smaller Bots. that technology hadn’t been used in decades.

“The obstacle course changes shape and obstacles each time it is used, according to the wishes of the Mentor in charge of each team. However, it has long replaced by virtual training, which has proven to be more effective.”

The tour around the grounds had taken about an hour, but they finished the entire loop and the robot led him back inside the dorm building.

Once inside, the AI said, “Your room is number 13 here on the first floor. It’s where we always put the new live-ins. The mess hall is on the top floor. If you have any more questions, please feel free to contact me.” The robot transmitted the door code and its contact information to Gabriel’s wrist-pad and sped off without even waiting for a farewell.

Gabriel walked to his room, anxious for a chance to start training with the Sentinels, and awed by what he saw that day. He was ready to dive into the files regarding his new teammates. He passed room after room until he came upon the door marked 13 Close to the end of the hall.

Entering the room, his wrist-pad beeping, he looked around at his newfound residence. It was luxurious, a large sitting room flanked by a fireplace with a marble table and bamboo divider between it and the bedroom - with a king-sized bed that looked likely to swallow him if he wasn’t careful.

He had a full-size bathroom with an elegant walk-in shower as well, the kind with multiple nozzles. He set removed his armor and flight suit and laid on his bed, willing himself to relax.

He tapped three times on his wrist-pad and the pieces on the floor floated together, then rearranged themselves back together.

Gabriel liked how easy it was to set his suit into sentry mode. The exo-skeleton was a security mech that would only answer to him. Now, would let him relax and focus on his reading in peace. The orbital cannon fired again, shaking the room and reminding him of the dangers that lay outside, floating in space.

Settling into the long blue sofa, Gabriel set to reading about the other members of his Strike Force.