Carving out the eleventh floor took The Core a long time. The final image of this floor in its mind's eye was quite vast and it wanted to fulfill it to the best of its capabilities.

  During this The Crazy One visited its dungeon once more, this time to ask what happened to the invaders killed during the expedition and The Only One.

  The Core only absentmindedly replied, too busy digging as it was but the answer must have been sufficient for the human left almost immediately after receiving it.

  Aside from this incident there was no entry into the dungeon which The Core couldn't be grateful for as it was too busy to even think about such matters.

  Like that it managed to carve out a pretty good chunk of rocks and various minerals that it didn't bother finding the name of, too excited to be rid of them in order to free up space.

  The Core looked over the framework of its new floor and deemed it not aligned with its vision so it remade a few untoward parts before looking over again and deciding it was now perfect.

  It filled the bottom of the floor with grains of sand, which were identical to each other, making it so there was a fine layer of it on the bottom while the section closest to the entrance to the 10th floor received a larger amount, making what right now seemed like a mount.

  That way it would actually look like a beach once it filled it with water.

  With that thought it proceeds to prove itself correct by filling the basin with large amounts of water.

  The Core felt proud while looking over the newly made beach.

  The rock ceiling, present on all its floors, greatly diminished the beauty of the empty of all life floor but The Core couldn't notice for it only saw the sky as a monument of stagnation and not something to aspire to recreate.

  With satisfaction it began to conjure monsters to fill the water with. Unlike in the third floor it wasn't going to use mundane fishes to blend in the danger, instead it will solely create highly dangerous monsters.

  This tale has been unlawfully obtained from Royal Road. If you discover it on Amazon, kindly report it.

  The Invaders would need to either swim over or walk underwater to cross the floor and giving them the opportunity to use the ordinary fishes as a hiding spot seemed inefficient.

  Although it could choose instead to create less, depriving Invaders of this safety net while also offering its monsters a higher chance at ambush.

  The Core mulled it over and then decided to conjure small schools of ordinary fish, so that not even halflings could use them as cover, before looking at its monster catalogue.

  It felt exasperated seeing so many blueprints of humans with little variation between but dismissed the emotion quickly before focusing on its underwater monsters.

  There were a lot but The Core decided to not use all of them, wanting to save some for its ocean floor that it already planned out.

  There were also some new ones that it only unlocked now due to it fulfilling its advancement task.

  The Core felt happy seeing the blueprints as they contained many creatures that it couldn't possibly gather a sample of due to its location such as the Dieflig squid that lived in saltwater.

  It was tempted to purchase it and add it right now but they hunted in packs and were also quite large which made them unsuitable for the beach floor that was supposed to be varied.

  Furthermore it decided that the requirement that monsters needed to fulfill in order for it to use them to populate this floor should be small sized and capable of long ranged attacks.

  The first requirement was because it made the floor large but not large enough to be able to house huge underwater monsters, of which there were a lot.

  The second was because it didn't think there was any Invader that could outswim a monster fish and catch it.

  Although there was also a large amount of underwater monsters that specialised in close combat that could utilise their fast speed and agility, which should be considerably higher than their opponent due to the environment, for hit and run tactics, it chose to save them for later.

  They were going to go to the next floor.

  So with a new checklist in mind it looked through the catalogue once again, steeling its mind whenever it saw a new, shiny option that could work with water, reminding itself that it was going to be used once it was finished with this floor.

  It ended up with a lot of new monsters, including but not limited to Nescrutable Blennioidei, Runic Sprat and Skyr Herrings.

  There wasn't any plant life on this floor but The Core decided that it wasn't really important and instead began working on the entrance to its twelfth floor.

  It was going to move its main component, the core, when it was finished with its expansion or when invaders struck, before that it was content to keep adding more floors.