Abyssal Sovereignty

“...!”

A guttural, incomprehensible sound erupted from the mouth of the "Plant Cthulhu." It was clear it was enraged—after all, it had been struck back by a being several times smaller and seemingly weaker than itself.

In retaliation, it extended its tentacles, lashing out at Yverantheia, who had landed on the ground. Despite its massive size, the Plant Cthulhu was surprisingly fast. The force and speed of its tentacles easily shattered the rocks they struck.

However, Yverantheia was not to be underestimated. She deftly evaded the attacks, then leapt onto one of the tentacles and began running along it. The Plant Cthulhu, refusing to let her get close, swung its tentacles violently, slamming them into the ground repeatedly.

Yverantheia, seeing the futility in staying on the tentacle, jumped back to the ground and quickly set up numerous magic circles. Fireballs, water blades, and lightning spears—all manners of elemental magic—assailed the Plant Cthulhu.

In this world, there existed a concept known as "elemental affinity." Different creatures had varying affinities with elements like fire, wind, or space. However, this didn’t mean they couldn’t use other elements. According to a theory proposed by a certain witch, this was due to the unique nature of souls, which affected the efficiency of converting different types of elemental energy.

As a former Saint of the Holy Light Church, Yverantheia naturally had an affinity for the light element. However, her inherent skill had allowed her to absorb parts of various monsters' powers, thus increasing her affinity with other elements as well.

"It doesn’t seem very effective," Yverantheia noted.

Though plants were typically weak to fire, the Plant Cthulhu, being both a plant and a sea creature, had a natural resistance to fire.

"…!!"

The Plant Cthulhu grew even more furious at Yverantheia’s magical attacks. It controlled all its tentacles emerging from the sea, sending them crashing toward her.

Despite the onslaught of tentacles creating a near-impenetrable net, Yverantheia remained unflustered. She dodged continuously, sometimes sidestepping, sometimes leaping away.

During one such evasion, Yverantheia leapt into the air. Seizing the opportunity, the Plant Cthulhu directed multiple tentacles to grab her.

Yet, in an instant, she vanished.

"...!?"

A moment later, one of the tentacles near what seemed to be its chin was severed.

"First time using this... not bad."

Hovering in front of the Plant Cthulhu, Yverantheia stood in mid-air. She had utilized a different application of her mana manipulation, creating platforms beneath her feet to stand in mid-air. While not true flight, it was sufficient for combating the Plant Cthulhu.

"…%&!!"

Within seconds, the Plant Cthulhu regrew its severed tentacle. Its roar, now imbued with a psychic attack, reverberated through the area.

While psychic attacks were unique, their effectiveness depended on the target’s mental fortitude. Having endured numerous hardships, Yverantheia's mental resilience was exceptional, even among other peak fourth-level beings. Thus, the Plant Cthulhu's psychic attack had little effect on her.

"My turn," Yverantheia declared.

Bending her knees and using the mana platforms for support, she launched herself towards the Plant Cthulhu's head, striking the same spot as before. This time, her punch carried even more force, driving the Plant Cthulhu back into the sea, its blood staining the water purple.

Yverantheia stood on the now-motionless Plant Cthulhu, catching her breath and assessing its state. Suddenly, numerous tentacles came alive, ensnaring her.

"%&!"

The Plant Cthulhu rose again, revealing its entire body hidden beneath the surface.

‘So, the weak spot isn’t the head?’ Yverantheia pondered.

Despite her powerful blow penetrating the Plant Cthulhu’s head, the real weakness lay in a crystal encased in hardened vines beneath its body.

The tentacles coiled around Yverantheia began to tighten, the pressure threatening to crush her bones.

‘It’s trying to crush me...’

Yverantheia mustered her remaining mana to reinforce her body, resisting the increasing pressure. However, the Plant Cthulhu, a sixth-level behemoth, was far stronger than her fourth-level self. Her resistance weakened quickly.

"%&."

Seeing Yverantheia’s struggle, the Plant Cthulhu lifted her towards the exposed crystal, the smaller tentacles retracting to reveal it fully. This was its method of consuming prey, absorbing their energy directly for maximum efficiency.

"Finally revealed, huh?"

As she neared the crystal, Yverantheia muttered, and a surge of mana erupted from her. The Plant Cthulhu sensed the danger too late; a massive explosion of mana radiated from Yverantheia, forming a blinding white fireball. The heat was intense enough to evaporate the surrounding seawater, and the shockwave toppled the sparse trees on the mountain.

From a distant fortress, Goblins, Smurfs, and Ogres shielded their eyes against the intense light, bracing themselves against the blast. Without the fortress, the casualties would have been unthinkable.

The explosion lasted several minutes. When the light faded, Yverantheia stood amidst the scorched remains of the Plant Cthulhu’s vines, the crystal nowhere in sight.

“Indeed, the Ogre King’s precognition skill is quite useful,” she remarked.

Yverantheia had foreseen this outcome from the moment the Ogre King mentioned the powerful enemy. Using the borrowed precognition skill, she had glimpsed fragmented visions of herself exhausting her mana in a futile attack, only to be devoured by the Plant Cthulhu's hidden weak spot.

Armed with this knowledge, she had prepared by storing a portion of her mana with the Smurfs’ technology and feigned weakness to lure the Plant Cthulhu into exposing its crystal. Then, she detonated the stored mana in a decisive blow.

While Yverantheia sought strength through genuine combat, she hadn’t forgotten her ultimate goal. Dying needlessly was not an option.

Suddenly, she felt her body and mana rapidly recovering.

“This power... I’ve advanced.”

Stepping on the charred vines, Yverantheia leapt back to the land. She quickly assessed her current state and began making her way back to the fortress.