The shark-eel-looking creature had needle-like teeth, a ribbon-like dorsal fin with spikes coming out of the dorsal fin. As the creature continued into her territory at a fast pace, Amy realized that this was not just a visitor to her territory.

That was when Amy tried using the method that she has been using with creatures crossing into her territory, the mana strings. But every time she tried to do it, the mana strings would just bounce off the creature's skin.

This was the point that Amy started panicking. She tried to stop the creature with mana strings. Unfortunately, the hydrius salamanders were off exploring the reef. She only had predatory fish left in her territory that she could move fast enough to defend against the incoming creature.

So Amy issued a command to defend and attack the creature, and they attacked. The ice barracuda's slammed against the creature, and the glass jellyfish were too slow, and the creature avoided it. Unfortunately, it had little to no effect on the creature, and it honed in on the tunnel and began to traverse the tunnel.

Quickly, the shark-eel-like creature reached the tunnel room, and Amy prepared the creatures, plants, and monsters within the dungeon to defend, attack, and stop the creature. She also warned Calder that something was invading the dungeon and to hide until she gave the all-clear. Amy anxiously watched the creature enter the portal and fall into the water of her dungeon.

As soon as the shark-eel-like creature acclimated to the sudden drop and water change, it started heading in the directions of her core. Within seconds, a grouping of arctic bass led by an arctic king bass was swimming by, and the creature shredded through half of the fish before the group could react. This demonstrated that Amy would need her creatures that could attack or defend themselves to confront the invading creature.

After the shark-eel-like creature swam a couple minutes unobstructed into the centre of the dungeon before it met one of her monsters. The creature met an augment penguin, one of her penguin monsters that can temporarily increase its size and muscles to attack. And attack, the penguin did.

It caught the invading creature by surprise, smashing into its middle and severely injuring it. In response to the augment's attack, the creature swung its head and latched onto the penguin, using its razor-sharp teeth to grip onto her penguin.

The augment penguin took one of its wings and started smashing the creature's head, trying to make it let go. The penguin still had its enhanced strength, so after a few wacks, hitting the right spot, smashed the shark-eel-like creature's skull in.

When the creature died, it relaxed its jaw and let the augment penguin go. The penguin came out of the fight with deep cuts on its torso that were bleeding heavily.

Amy, who was exceedingly happy that the augment penguin killed the shark-eel-like creature, that she decided to heal the penguin. Amy pulled a mana string from the circulating mana, inserted it into the penguin, and used her mana to increase the penguin monster's healing ability to rapidly heal the injuries. Within minutes, all that was left of the fight was a series of fresh scars on the penguin.

With the penguin healed, Amy turned her attention to the corpse of the shark-eel-like creature and absorbed the creature. When she absorbed the creature, a blue screen appeared.

You have absorbed and added the monster, Honru Shark, to your dungeon.

'So, that's why her mana strings bounced off its skin, and what the creature was called. Now, let's see the description,' murmured Amy to herself as she pulled up the description.

Honru Shark

A type of aquatic monster commonly found in cold-water oceans and near large food sources.

Rank Level: E

The monster's description appeared the same as the other descriptions she had seen, except there was a rank level. Amy assumed this declared collectively how dangerous a monster is. But it wasn't something that she had seen on her penguin monster descriptions. So, she pulled the monster descriptions of her penguin monsters up to see if they have ranks too that originally did not show up.

Penumbra Penguin

An evolved monster from the yellow-striped penguin, this penguin hunts in the shadows and stalks its prey before attacking when least expected.

Rank Level: F

Augment Penguin

An evolved type of monster from the yellow-striped penguin can temporarily increase its muscles to attack or defend itself.

Rank Level: F

Archer Penguin

An evolved type of monster from the yellow-striped penguin, it has fast-growing, deadly sharp, arrow-like feathers that it uses to fling at its enemies.

Rank Level: F

Amy perused the three descriptions and saw that each of the penguins was level F, so by her knowledge, a level below the honru shark in rank level.

It seemed to her that the augment penguin must have got a lucky shot in order to kill the shark monster, who was a level above the penguin in danger level.

With that, Amy let the creatures under her domain relax back into their normal level of vigilance and informed Calder that it was safe to move around again. When she did this, another blue screen popped up.

You have reached the requirement to obtain a second floor.

Accept to add another floor at this moment.

'I accept,' thought Amy. When she did this, another blue screen popped up.

Floor installation will begin in:

Three

Two

One

After the countdown, Amy's core started to ache, kind of like the growing pain ache that she had when she was a kid, and she felt her involvement become frozen. She could still see both within the sub-dimension and her territory, but she could not interact with anything. The growing pains increased for a couple of minutes before Amy sensed movement of her core and the increase of her sub-dimension. She watched as her core started to grow bigger until it grew a full centimetre, making her core a total of 4.5 centimetres in length.

As her core grew, so did the sub-dimension. Amy watched as the growing pains began to get more intense, as the sub-dimension grew an additional 100 metres side to side and an additional 50 metres top to bottom.

When both her core and her sub-dimension stopped increasing in size, the pains that she experienced stopped, and Amy was finally able to interact with her territory and new floor within her dungeon and sub-dimension.