There were many icons waiting from him. He checked the first by focusing on it, which caused it to expand into a system window.

Skill learned: Awareness

Type: Cognitive

Rank: Rare

Level: 20 / 20

You have greater awareness of your surroundings.

Skills were abilities recognized by the tower.

One of the ways to acquire them was by doing something well enough for the system to acknowledge it, whence it also gave it a rank and a level. The rank depended on the skill itself, and the level was based on how well you knew the skill up to the theoretical max created by the system—twenty for rare skills.

Luke's memories told him that albeit difficult, you could learn more about a skill you had maxed. The tower just didn't give you another level for it.

The thing you did had to be at least somewhat out of the norm to be accepted by the tower, as there were no skills for walking or breathing normally. Also, things that were controlled by stats, like movement speed, were very seldom affected by a skill. Stats were considered almost special skills common to all living beings, with no level limits.

He had learned the Awareness skill by using his knowledge of physical combat to analyze his opponents and being aware of his surroundings in the fight. That's how he had been able to tell how Miller's left leg had an issue just by the way the boy had been holding his arm.

Awareness was considered a great skill in the tower. Some even called it a substitute for perception, a stat in some of Earth's games that didn't exist in the tower. It was still on what was called "mortal realm" though. Anything below the Arcane rank, the fifth rank out of ten, belonged to that realm. Only from that rank onwards did really incredible things became possible.

To be fair, his Awareness was on supernatural levels by Earth's standards. It was just nothing special in the tower, especially not if mana skills came into play.

He checked the next icon.

Milestone reached: First Cognitive Skill

You've learned your first cognitive skill.

Reward: +10 SP

Khan bonus: +1 SP

Milestones were like breadcrumbs the tower threw to everyone. It wanted people to follow certain paths, usually to generate conflict, and those who took the first step on said paths were rewarded for it. Everyone could reach the same milestones, and they all gave exactly the same reward, 10 SP, no exceptions.

At least that's what Luke had believed until now.

He had no memory of any modifier at all that could be applied to a milestone. However, it seemed being a Khan Honorary Citizen...

He frowned.

He knew he was a Khan Honorary Citizen. He knew the only known way to get it was as a reward. However, he had no idea what he had done to get that reward, or when he had gotten it. In fact, he didn't even know what a Khan was, only that it was likely a nation.

What the hell was going on?

Could it be related to the "recent memory loss" mentioned in the very first system message he had gotten? He didn't remember forgetting anything—duh—so maybe the missing memories were from the ones he had received.

What else could be missing?

He shook his head. If the memories were missing, they were missing. He had a lot to deal with already and couldn't waste time wondering about stuff beyond his reach. He just went back to analyzing the messages.

As a Khan Honorary Citizen, he had received bonus SP upon reaching a milestone. That was great news. Sentinel points could be used to increase people's level and stats, improve their skills, and, in the tower, even to buy some things. Everyone was always missing SP, and as one of the weakest non-demonic race, humans had it even harder...

His frown deepened, and he suddenly found a very, very huge hole in his memories.

Luke had no recollection of ever being in the tower. Yet, he had a lot of memories about humans in the tower in general, like what their average stats were, and even of their opinions about tower stuff.

Could his memories be... from a human who had been kidnapped by the tower in advance? Or could another world with humans, if that was even possible to exist, have found a way to send their collective memories to him?

His theory made some sense. He had enough memories for many lifetimes, too much for a single person to learn. There was also some distinct... How could he call it? Humanness to the memories, in a way that he felt it had belonged to humans before. And the next system message confirmed his theory.

Achievement unlocked: First Cognitive Skill

You're the first human from Earth to learn a cognitive skill!

Reward: +100 SP

Khan bonus: +10 SP

The achievement message said he was the first human from Earth to unlock it. The tower recognized each species or race as a single people for achievements. It only specified which planet the race was from if the same race was already in the tower.

Strangely, though he couldn't recall just "humans," he did have memories of a race called high humans, and even of arcane humans being in the tower.

He was frowning really hard now. His memories were clearly much more mysterious than he had initially thought. How had they reached him? Why him? Who the hell were the Khan and why had he become an honorary one?

He shook his head harder and stopped frowning. He could think about that later. Now, he had to understand his situation better and plan for the immediate future: how to protect his granddad from Jackson.

Unlike milestones, achievements were unique to each society. No other human from Earth could unlock that achievement after Luke had gotten it. They all gave at least 100 SP, with some giving a lot more, and he knew just what to do to get many of them.

That was a possibility to explore later. He could accumulate SP by getting achievements and become some sort of demigod by Earth's standards by spending it the right way. Though it wouldn't make him immortal, it might help him in many things. Becoming a famous international athlete should give him even more protection from Jackson than just becoming a good doctor. And it would certainly make his mother proud too, right?

Anyway, seeing things like skills, milestones, and achievements told him the system was here to stay.

Suddenly, the idea that it was just the prelude of something bigger made him shiver. The tower was evil and kidnapped entire civilizations. Could his memories be a warning sent by a human civilization there, wishing for people from Earth to be ready because they were next?

Luke started feeling he was way out of his depth. He was just a sixteen-year-old coward, a poor guy who didn't even have money to eat plenty. In fact, his stomach was rumbling right now because he had missed lunch. What could he do to save Earth from the Sentinel Tower's claws?

He focused on breathing and running for a while to calm down, and then put it out of his mind too.

'No use thinking about things out of my reach now. I'll cross that bridge when I come to it,' he repeated to himself over and over again.

He checked the next icon.

Title received: Pioneer

You're the first human on Earth to pass the TEsT_fL00r— ERROR!

The text changed while he was still reading the message.

WARNING! FURTHER SECURITY BREACHES LOCATED!

The HIDDEN_EMPEROR_PROTOCOLS temporarily acting as Tower Overlord have determined the Test Floor was also part of a demonic ploy to bring despair and push new races toward the Demonic Horde.

The Test Floor has been purged. Its creators will be reported and investigated.

Furthermore, the currently engaged EARTHS_DEFENSE_PLAN has no floors. Adaptations deemed necessary. All system messages will be changed accordingly.

He had barely finished reading the text when it changed again.

Title received: Pioneer

You're the first human on Earth to unlock an achievement.

As a Pioneer, your future will certainly bring you in contact with other races, and the language barrier might bring issues.

Thus, the Sentinel System has given you a gift to make your path easier.

Reward: Universal Linguist skill at max level

There was so much to absorb in there that Luke forced himself to stop running and think.

He started with the most important part: EARTHS_DEFENSE_PLAN. That was a computer-like way of writing Earth's Defense Plan. The Sentinel System had a plan in place to defend Earth.

'WHAT THE ACTUAL FUCK?' he screamed in his mind.

What could the system even want to protect the Earth from?

The answer was obvious: the Demonic Horde.

The Demonic Horde was coming to Earth.

Suddenly, all his worries about Jackson felt way too small. Hell, his worries about getting a profession sounded outright stupid. Demons might already be on Earth, and he was wondering how to use the system to get a fucking job.

What was wrong with him?

The warning message had been very telling. It suggested the Sentinel Tower existed to fight against demons, but that its system had been invaded and used by demons to their advantage. And now the demonic influence was being purged by the "hidden emperor protocols." It explained a lot of things in the tower according to Luke's memories.

Why it seemed to let people grow stronger, but never strong enough to wipe out demons. Why there were demonic items that could hide from the system when people were supposed to destroy anything demon-related on sight. Why demons were sent to hell and forced to stay a long time there when they were killed, instead of getting permanently destroyed.

Why the Hell Floor existed at all and the tower would send races there if they failed to clear the tower with enough achievements.

Luke shivered when he thought of the Hell Floor. He had no recollection of it, only impressions, but he was sure he never wanted to go there. His very muscle memories told him he would rather face eternal oblivion than suffer for even a minute in that place. He didn't even know muscle memory could feel fear.

That news changed everything. He had to prepare not for Jackson, but to fight demons. And he had to do that as quickly as possible. In fact, he had to get to his grandpa and get him out of the city as quickly as possible. When the Demonic Horde attacked, it went for highly populated areas first. He had to bring his granddad to the middle of nowhere ASAP. That meant running while carrying his granddad.

He checked his total SP, 121.

'Level up and split all remaining SP into the four physical stats,' he ordered the system.

The message he got was nothing like he expected.

COMMAND ERROR!

Earth's mana levels are currently too low. SP operations are on hold. Manual training methods have been prioritized and still work.

The Sentinel System is currently increasing Earth's mana levels.

Time until Earth's mana levels reach the threshold for the Sentinel System to become fully functional: 6 months, 13 days.

That wasn't just bad, it was also terrible. Bad because his SP were all but useless, and terrible because he didn't want to know what "becoming fully functional" meant.

Yet, it gave him... peace.

Humankind wasn't ready to fight against mana-enhanced monsters, but the mana-less races of the Demonic Horde were weak enough that they could be dealt with using firearms. Earth was relatively safe for 6 months, but how the hell increasing Earth's mana levels would help protect it was beyond his understanding. For all he knew, keeping the world relatively mana-free would help keep it safe. Maybe the Sentinel Tower was still under demonic influence and the hidden protocols didn't even realize the danger of what it was doing. Or maybe it just knew something he didn't.

Of course, some humans might already be under demonic influence, but from what he knew of Jackson and his goons, that wasn't very different from what humankind already did to itself on a daily basis.

Another thing he liked to see was how being a Khan Honorary Citizen gave him access to exclusive information. He would be totally in the dark if he didn't got those messages. And he would make full use of the information it had given him.

He had 6 months to prepare for the system getting fully functional. Jackson suddenly wasn't such a minor issue anymore. The demons were coming, but for now, he had to survive his own local tyrant.

Luke resumed running and checking his messages.

Skill received: Universal Linguist

Type: Cognitive

Rank: Uncommon

Level: 15 / 15

You can understand and use the languages of other races connected to the Sentinel System.

It was normal for merchants and Tower Climbers to have that skill. Most people didn't learn it though, so it was kept at the uncommon rank despite being relatively widespread.

There were ten skill ranks total, and they could be related to either the overall quality of a skill, its rarity, or both. The quality was the most important, but if enough people knew something, its rank dropped. The common rank was the worst, followed by uncommon, rare, runic, arcane, epic, legendary, mythic, transcendental, and perfect.

Common skills had a max level of 10, uncommon, 15, rare, 20, and so on.

It was interesting to note that in Luke's memories, the description of the skill said "other races in the tower." It seemed the changed messages the warning had talked about was already in place.

The skill left him wondering; theoretically, the human race was connected to the system through him even if no one else had access to the system yet—which he didn't know for sure. But if that was the case, could he understand German without having ever studied it? Or would he have to wait for a German guy to connect? Did the tower consider German people a different race from his?

That was easy to check.

"Hallo, ich bin Luke," he said in German. "Oi, eu sou o Luke," he then said in Portuguese. And finally, he tried Japanese. "Kon'nichiwa, boku wa Luke-desu."

That was cool as fuck. All that knowledge had been placed into his mind during the fight, and he hadn't even noticed it.

How did the system even learn languages anyway?

The tower, or rather the system, dealt with the mind as little as possible. The Universal Linguist and the Awareness skills were two of the relatively few cognitive skills he knew of. Skills like mind reading, mind controlling, tactics or strategy simply didn't exist, which was both a blessing and a shame.

He moved to the next icon.

Milestone reached: Max a Skill

You've reached the maximum level of a skill for the first time.

Reward: +10 SP

Khan bonus: +1 SP

That was a pretty common milestone to reach, especially when it could be done with any common skill.

Unfortunately, the Max a Skill milestone had no associated achievement...

Achievement unlocked: Max a Skill

You're the first human on Earth to master a skill!

Reward: +100 SP

Khan bonus: +10 SP

Luke had no recollection of that achievement. Did it mean that whoever had sent him the memories was ignorant of it too, that his memories had holes like that, or did the changes to the system also affect its functioning, making it more generous?

If it was the latter, what else was different in the system?

At least this change was good for him, and less demonic influence should mean more good things coming, but who knows? He would wait and see.

Also, it was pretty obvious now that his Khan bonus for milestones and achievements was either 10% the base reward or a set value. He was hoping for the former, but it was good either way.

Skill learned: Unarmed Combat

Type: Physical

Rank: Common

Level: 10 / 10

You can fight without weapons.

Skill learned: Armed Combat

Type: Physical

Rank: Common

Level: 10 / 10

You can fight wielding weapons.

When his memories resynced with him, Luke had become a master of many weaponless martial arts and other fighting styles. Yet, the tower only gave him two skills. Most common and uncommon skills were generic like that. There were so many people who learned at least some fighting style in the tower for self protection that, unless one of them was really special, they all became just the Unarmed Combat or Armed Combat skills in the common rank.

It was a bit silly to get the Armed Combat skill for swinging a trash bin and holding a knife, but well.

Leveling skills could be done in two ways, manually, by understanding and using it better, or by spending sentinel points. The latter directly injected knowledge into the person's mind, and different ranks and levels came with different costs. The resync and title had given him total mastery over the skills he had learned, so he wouldn't have to worry about it anytime soon.

Milestone reached: First Physical Skill

You've learned your first physical skill.

Reward: +10 SP

Khan bonus: +1 SP

Achievement unlocked: First Physical Skill

You're the first human on Earth to learn a physical skill!

Reward: +100 SP

Khan bonus: +10 SP

The milestone and achievement were expected, and their reward was useless for now.

And that was it. To sum it all, he had become a polyglot elite fighter, gained a bunch of useless SP, and learned of Earth's impending doom. Definitely not just another Tuesday.

Now, he only had to find out whether his grandfather was okay before deciding what to do with his life.