Calculator Cube

"The invitation that all individuals allowed to enter the Calculator Cube are given."

- You're qualified to come to the Calculator Cube! Come get your ultimate weapon!

About
The Calculator Cube is a mysterious subspace located near the border of the Monster Realm and human nations, though its exact location varies. This strange place seems to contain many items of great power destined for a select few, and because of its mysterious origins it is said that it was created by a God. When a person meeting the "right qualifications" appears, they are sent a message through their dreams, where a yellow bird appears asking them to come to the Calculator Cube accompanied by their "soulmate" in order to receive their ultimate weapon, whatever it may be. The dream also mentions a number that is necessary to solve the Cube and succeed in obtaining the artefact.

It is an odd place unlike any other in the continent, as its walls and floors are not made up of any material substance but rather strange orthogonal green lights crossing each other. Its doors are made of solid purple light, and perhaps due to its proximity to the monster realm it is filled with dangerous monsters like the Vevetar. Its most notable feature however can be found in its four corners, where the floor is made up of odd tiles numbered much like dice with all the values between one and nine. If one steps only once on the different tiles until reaching the value mentioned in the dream, the adventurers are warped back to the center of the maze after getting the congratulations of a mysterious voice, and if this is done on each of the four corners, the way to the weapon opens.

So far, the only known individuals chosen by the Calculator Cube are Sill Plain who received the powerful magic gloves named Sillpheed, Shizuka Masou who obtained the magic staff known as the Crystal Rod, and Kanami Kentou who obtained the aptly named Decapitation Blade. On their quest to find their weapon, they were each accompanied by their soulmate, the strange warrior known as Rance.