After leveling up skills for several weeks, the hamlet Julian is staying in will come under siege from waves of monsters fleeing...something. He will be the primary defense, and his increased levels will allow him to create weaker undead at a faster rate. The regular smilers fall easily, but he struggles in a boss fight against a Greater Smiler -- about the size of a nobleman's carriage. Losing most of his undead, he is able to acquire the beast, and resurrect it. More waves of medium-to-strong beasts occur, but he never struggles like he did against the greater smiler until the Voidling shows up.

Voidlings aren't fully under the control of the system. It tries to impose its rules upon them, but they are the Void given a semblance of form -- the very thing that destroyed Julian's original universe. Voidlings are weak enough that the System can force some order on them though. All of a Voidlings stats have to be reduced to zero in one round in order to kill it -- anything less and it instantly reforms on its next turn.

Julian struggles, and the creature annihilates his lesser undead with ease. By this point he has acquired multiple Greater Smilers, however, and with the combined efforts of the greater undead, the surviving villagers, and collapsing the village gate on the creature, they just barely finish it off. A ripping tear forms in reality for a fraction of a second, a horrifying but ultimately harmless apparition unless one is caught inside. The Voidling's corpse vanishes into it.

The village nurses its wounds, and Luna finally arrives with reinforcements -- they are bloodied and wounded from fighting other Voidlings and even greater Void-things. From here, Julian departs into the Wilds proper, his strength finally enough to survive. He spends the next several years training, first under Luna, then when he catches up with her, becoming a Lord-tier entity, under her own master. Eventually he's on the cusp of the King-tier, and with their master's permission, he and Luna break out into the greater world beyond the "egg", as it's called by greater adventurers, around the Town of Beginnings. He controls a true army at this point, and has unlocked access to both spirits and skeletons, earning him the combined skills Create and Control Undead. His undead monstrosities are combinations of corporeal and spiritual entities, the Lords among them capable of spreading the undead plague and controlling yet further undead.

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He's no great powerhouse in this new realm he now explores, but he's not weak either. He and Luna eventually cross the threshold into King tier (400 levels), and they continue to gain strength. They found a settlement close to the border to the next band of the world, garrisoned by the undead and other summoners' forces, and decades pass as they gather strength, with focus given to noteworthy adventures. They reach the cusp of the Divine tier, and they enter the next band of the world.

Here the majority of adventurers are king-tier, with the divines ruling. Voidling incursions are frequent, and failures at this layer allow incursions deeper into this world. As they cross into the divine tier, they notice "glitches" in how their abilities interact with the System -- their abilities start working less like game powers, and more like real powers. Simultaneously, they stop being able to grow the powers they aren't well-known for. Eventually levels vanish from their status sheets entirely, and all they see is what they are known as to the world: The Undead Plague, and The Lunar Arrow. Void-beasts at this zone are barely restricted by the System, if at all, but it doesn't matter -- their own powers are able to overcome the creatures.

Void-beasts are the majority of what they fight now. Eventually, a greater incursion occurs. They don't know why, but the next layer of the world is shattered, and the void invades. But at this point, Julian's hordes stretch from horizon to horizon, and Luna's arrows can pierce the world itself. The Final Battle ensues, billions dying from every layer of the world as they are forcibly recruited by the various Divine factions in hope of salvation. The System is dying. Unending hordes of undead, supported by arrows that appear as laser artillery fire, do battle against creatures that barely exist, and what does exist violates the rules of reality.

Eventually, the forces created by the System emerge victorious. A divine pantheon, most able to maintain their own pockets of reality, split off. Several create their own Systems, modeled off of the one that created them but "improved" in various ways. Julian creates a deal with many of them, attaching his own power to their worlds, protecting them in exchange for the power of death they generate, while Luna acts as a sort of wandering divine guardian.

Every several eons, if time can even be measured with how they experience reality, Julian and Luna encounter each other in defense of a world against a particularly nasty incursion. Their ever-increasing strength is matched by that of the Void, but the age-old companions still appreciate the opportunity to spend a few centuries together in nostalgic battle ensuring the continued existence of reality.