The child knew that now was the time to change their core room.

With the repeated expansions of their sub-dimension and the increasing size of their floors, any invader meaning harm to them and their core would probably get through their core room quickly. Even though they have ice poles making maneuvering difficult, their core room is only six metres high and three metres wide.

And that will not work.

It's too small to adequately defend at this point, and with Dwyn being around, the child needed a bigger room for both defence and their undine.

Removing all of the ice pipes connected to the walls, laying them on the ground, and transplanting the plants, animals, and monsters to other floors where they were present, the child started expanding the room.

As they dug out their core room, the child didn't make it straight or have perfectly evened sides. They kind of just went with how the ice flowed, all bendy and curved, making a room that looked natural other than the smoothness of the surface.

Their core room ended up being 30 metres long at its longest point and 20 metres high at its highest point, and the child was delighted with how it turned out. And they had plans for their core room.

The child kind of wanted to mimic their floor environments into their core room, but not really.

In their head, they wanted to merge and smush together a bunch of different environments into one. Still, realistically they knew that it would be very hard.

So they created two ridges along the bottom of the floor.

The first ridge, located a metre away from where they intended the new entrance location to be, rose 11 metres high and spanned three metres in length. It had a slow incline from the bottom of the floor to the top of the ridge.

The second ridge rose to just above nine metres high and spanned ten metres long. With this ridge, the child made the ridge like a cliff, coming straight up from the bottom of the floor.

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It was with these ridges that they were going to use to help create and differentiate the environments that they had within their dungeon into their core room.

Grabbing multiple water mana strings, the child set them circulating along the room, slowly filling the room and creating a mixture of fresh and saltwater. Just as the water level reached seven metres high, the child opened up several small tunnels leading from multiple floors to bring in more salt water.

Metre by metre, water flowed into the room before the child closed up the tunnels once it reached just under 11 metres high.

The child began working on the different environmental elements, with the water being a nice mixture of salt and freshwater and all of the base elements of their room being satisfactory enough with what they wanted.

They wanted to have an island environment, a mangrove forest with a seaweed base, a coral reef surrounding the island, a couple of empty areas and a kelp forest.

The child required a different base for each environment to cover the hard ice floors.

With the island, there will be about a metre or so of soil for their non-aquatic dwelling plant species.

They wanted to make a kind of sandy soil for the mangrove forest. A mixture of sand and the soil that layered the ridge will provide both the nutrients from the soil part of the mixture and hopefully create more of a murkiness for that area specifically.

Their coral reefs will have an all-sand component, along with their kelp forests. Their kelp forest will have large boulders and large stone-like chunks of pressurized ice.

The few small empty spaces that they plan to be littered with a mixture of sand and various-sized pressurized ice rocks.

So they got to work with what they could. With no readily available access to a sandy environment not within their dungeon right now, the child knew that they would most likely have to wait for the storm to end or figure out a way to produce sand before finishing their core room. But they can most certainly start with the island and try to mix the sandy soil they wanted for the mangrove forest.

Opening up another tunnel, the child began scooping handfuls of soil and tiny soil organisms that made the soil healthy onto the island. With each scoop, the child packed it onto the island, slowly inclining from where the water touched the island's edge to the middle, where the most significant amount of soil is located.

With a bit of finicking and the use of mana strings, the child used one mana string to make a small weaved net that they pulled tightly across the three-metre circle of the island and secured to the underlying ice. With a bit of experimentation, the net allowed the soil to stay on the island and only get pushed into the water when there is an outside force doing so. In the child's mind, this was a great way to separate the environment and keep any soil from slowly falling into the water.

As they were creating the net, they felt Dwyn poke their head into their core room with a giggle before curling up back in her den. Her appearance reminded them that they needed to change her den. Whether now or later, they will have to merge Dwyn's den into their core room.

Just as they were considering whether the den should be separate from the room itself or within the ridge, the part of themselves that was paying attention began rapidly ringing an alarm like never before.

With a whip of their body, the child almost gave themself non-existent whiplash as they rushed to what was the cause of the alarm.

Eyes wide with horror, they stared at the oncoming cliff that they were being pushed towards with increasing speed.

With their eyes closed, the child braced for impact.

Like the iceberg was gaining more speed, the closer they got to the cliff, they hit it with a series of bangs and crashes as the iceberg shook and groaned at the impact, almost like the ice was going to split apart.