Situated behind a thick stone door, the boss room gained its name due to the notoriety of the monsters that spawned inside.

While late stage third rank monsters appeared outside, the boss that spawned inside the passage further downwards into the dungeon always had the same strength, a peak third rank beast.

Technically there were only three minor stages within a rank, early, mid and late - roughly ordering monsters and people according to their accumulation of mana and aura.

It gauged their progress toward the next rank and had no formal requirements or notable features.

Yet the term peak was only used once a cultivator hit the limit of their current rank, unable to take another step forward without breaking through.

Without fail, the beasts that guarded the boss room had peak third rank strength.

Nisha followed the main path of the fifth floor and kept to herself when she met other adventurers.

Some parties returned from the depths and hauled their gains back to the surface, ready to sell off their loot and party with their shiny coins until the tension of fighting with their life on the line faded away.

Similar to the stairway leading towards the current floor, another small camp gathered around the stone door that sealed off the boss room.

Contrary to the rooms and corridors everywhere else, a thick barrier restricted entrance and exit once the fight inside started.

While it was not impossible to break through the stone doors with brute force, those capable of doing so were more than two ranks stronger than the beast inside and were better off simply killing the boss and moving on.

Nearly all adventurer parties got accustomed to following the convention of waiting for their turn and killing the boss to advance further.

After all, the arrangement was convenient for the dungeon delvers as well, where they could confirm their eligibility to survive on the lower floors.

 

Nisha nodded her head in greeting towards the other groups and sat down in an inconspicuous corner, resigned to wait for her turn.

Once the door opened and another boss appeared inside after the last team succeeded and moved downwards, the next group entered the room together.

While the participants moved inside, the boss itself would not take the initiative to assault them, with a few exceptions.

If too many adventurers piled inside or it felt threatened by an individual way above its own strength, the beast would make a preemptive strike.

Nevertheless, in either case the group had an overwhelming advantage and it was unlikely to cause losses.

Within a rather short time, three different parties filed inside the boss room and either succeeded in their fight and moved on or perished and contributed their cultivation and items to the Dungeon.

It was impossible to tell and even Nisha’s [Spirit Sight] did not manage to penetrate the shielded boss room.

There were several different paths leading downwards, varying every time the Dungeon closed and shuffled the floors around.

Usually, the upper floors had more passages and the fifth floor generally had between three and six boss rooms, allowing the ease of access.

Seeing that no one was around, the elf entered the boss room alone.

As it was inconvenient for her to appear alone inside the Dungeon, this was the first time the girl faced a boss, even though a peak third rank beast would likely not have been her match even before her recent advancement.

Carefully advancing through the stone passage behind the door, she soon arrived at the boss room itself.

Most of the rooms inside the dungeon were fairly spacious, allowing groups to engage in combat together.

Even then, this place was on an entire level altogether.

At least one third of the floor was submerged in deep water puddles, hiding unknown dangers.

The remaining stone floor was not quite even, but still possible to traverse.

Dense vines and water plants covered another third of the room, creating soft obstructions and foot snares.

 

Sitting half submerged in one of the deeper puddles, the head of the boss monster and part of its upper body easily told the dragon which beast she was about to face.

Glaring at the intruder, it's frame was big enough to intimidate adventurers on the same cultivation rank - about the same size as a pony.

Big bone plated legs squatted next to a sturdy frame, as well as countless pins making up a deformed back, accompanied by a mean glare and a bulging sound bladder.

Ever since the girl entered the room, its fierce eyes never left her movements for long, only scanning for additional dangers.

Nisha similarly spotted the boss and determined what kind of beast waited for her in combat, a [Hookback Bullfrog].

The beast was fairly well known and contrary to expectations, it was not a water element beast.

Growing on its back were countless pins of compressed earth, which were constantly nourished by the beast’s mana.

Once it engaged in combat, the true usefulness of them was shown.

Unexpectedly, the frog did not wait for Nisha to take the initiative, being targeted by a fourth rank dragon was enough to send a danger signal to the beast, which was much more perceptive than humans, who generally failed to pick up on the elf’s strength.

“Croak!”

Inhaling sharply, the sound bladder on its chest expanded furiously and sent a rippling soundwave throughout the room.

The utility of such a move was twofold, the noise was half a skill and disrupted the concentration of enemies, while the rebound from the expanded bladder was the second part.

Condensing all the physical power from the organ into one point, one of the hooks made from condensed earth, nourished for a long time with earth attribute mana, was propelled forward with sheer physical strength towards the girl.

The beast earned its name from the many protrusions on its back, which turned into magical projectiles equal to spells once they were unleashed.

Homing in on the dragon, the earth pin conveyed the true strength of the pinnacle third rank aura and mana at the disposal of a competent cultivator.

 

Generally, an adventurer party trained for long periods of time to attain the late third rank in either aura or mana depending on their profession.

Warriors purchased better equipment and trained their skills, while magicians perfected their mana handling and secured equipment suitable to supplement their strength.

Honing their teamwork through long periods of hunting on the fifth floor, they would eventually face the boss in its room once they no longer were able to attain meaningful improvement through the resources from late stage third rank monsters.

Nevertheless, the peak beast inside was still a great challenge to such teams and not every one of them made it through, many cultivators dying without a whole body left and their fates unknown as the Dungeon reabsorbed their equipment and energy.

Perhaps the girl would have struggled a tad to deal with the beast if the battle took place before her advancement, but now the struggle turned out to be nothing much.

Combining [Sidestep], [Turn] and [Retreat] into a single fluid dodge, the earth nail harmlessly sailed past the girl and broke apart the ground behind her.

Raising her arm and pointing her fingers at the beast, Nisha invoked a spell - [Fire Bolt].

She had not yet learned the fourth rank spell for the different elements, although she was comfortable casting the first three levels of each system.

Nevertheless, the girl was confident that the third level spell was enough to take care of the best, as she triggered the concept she comprehended during her breakthrough at the same time.

[Solar Flare] boosted the destructiveness of a fire spell to the extreme, akin to the eruption of plasma from the sun.

Natural markings condensed into the runes the dragon observed from the sun and covered her forearm, invoking the true power of the spell.

Nisha’s entire mana converged into an orange ball, sucking even the last drop of her available mana pool into a single point, hovering in the grasp of her fingers and drinking up the natural markings.

The [Hookback Bullfrog] froze in terror after it was locked on by the spell, interrupting it from launching a second earth spike.

It could feel its own death approach at the sight of the orange agglomeration of mana.

 

Although it sounded like a long time had passed, the elf actually took only a short moment to condense her entire mana into a ball, leaving her slightly drained from casting the spell [Solar Flare: Fire Bolt].

She had not expected that a single use would drain her of her entire mana pool, yet it was good news that the concept she comprehended was more powerful than expected.

Something apparently went wrong in the end though, as the natural markings did not only flow into the orange glowing orb, but formed runes around her hand and forearm as well.

Nisha had another spark of inspiration when she saw the development.

Although I saw the eruption and comprehended something from it, I also overlooked the source.

It looks like I forgot that I am not a celestial body!

Too late to change her actions, the dragon could only watch as the spell model was completed and burned through the entire stock of mana.

A giant eruption sent fiery orange flames forward, targeting the beast.

The spell no longer looked like a regular bolt, it resembled a humungous pillar of solid fire as it hurled towards the target.

Sadly, the recoil was equally huge and the elf’s forearm and hand was seared by a fiery impact, which ripped the flesh apart and sent bone chips flying to the ground.

As the elf inspected her mutilated hand, the flaming pillar of mana submerged the frog beast with unforgiving flames, wiping it out almost immediately.

Not even materials were spared and the entire body turned to ash that scattered with the dispersing energy.

Judging by the destruction and the lack of loot, ­[Solar Flare] was unsuitable to be used in a hunt inside the Dungeon, because it diminished the profit a party relied on to survive and upgrade their gear.

 

Meanwhile, Nisha wordlessly blinked down at her hand.

The injury was not grievous enough to deserve the term crippling, yet it was definitely impossible to hide back home and would take a while to heal regardless of her incredible healing capability.

Bone deep was the perfect term to describe the current situation, the recoil from using the concept together with her spell was too overwhelming.

Once the attack started, the elf realized that it was her fault for triggering the spell too close to her body; it did not have the same sturdiness as a sun.

Sadly, it was not avoidable either, it was the first time that Nisha used the power after all.

The pain was manageable as the dragon had sustained worse injuries before, it was only troublesome to try out her new prowess with having one hand disabled, and she would need to hide her wound when she returned to the Dharnas estate later on.

Right as the girl was troubled over an excuse to cover her hand and avoid using it, one of the essence blood drops inside the hidden space from the Dragon Heart moved and followed her circulatory system to the injured hand.

Countless golden strands returned to the dragon’s body, carrying the vitality, energy and healing power that was used up to condense it.

More damaged tissue, bone shards and charred splinters were pushed out of the wound, then threads formed around the limb.

Nisha waited until the itchiness vanished, then peeled off the dead skin cocoon from her hand.

New unblemished skin was found beneath, with no signs of a previous injury.

Inside the hidden space of the Dragon Heart, the formation of a fourth drop of blood essence stopped, new golden lines swam along the blood pumping through her heart and gathered in the place where the third drop used to be.

Based on the current speed, it would take two or three days until the essence blood regenerated.

Happy at learning a new capability of her Dragon Heart and gauging the power of her concept, the elf used some water from a puddle to wash away the ashy remains to cover her traces, then exited the boss room and walked down another flight of stairs.

The sixth floor of the Dungeon and new challenges awaited her!