Azure Paradox Infinitum

While Attuned to the Infinitum, you have a +3 bonus to attack and damage rolls made with this magic weapon. While you are attuned this ancient rapier, you can use it as a spellbook and spellcasting focus for your wizard spells, and you gain a +3 bonus to spell attack rolls and to the saving throw DCs of your wizard spells. It has 2 Forms, A hovering Box and a Rapier. While in its box form, it hovers around you until you call it to your hands. Additionally, while in box form, You can feed it pages of a spellbook or scrolls containing spells from your spell list in order to store and prepare spells in it as you would with a spellbook (This item does not stack with the other caster attunements). As a bonus action, you can speak the command word to alter the Infinitum's form to either the Box or the Blade. When becoming a blade, it appears in your free hand provided you have one, if not, it hovers within 5ft of you and acts as a "Dancing Sword". When becoming a box, it flies out of your hand and becomes a box and orbits around you. 

Azure Song: While in box form, it grants you advantage on Intelligence Checks and you can activate Bladesong without spending resources. While in Rapier Form, you have advantage on saving throws against spells and other magical effects, and spell attacks have disadvantage against you. Additionally, you give advantage to concentration saves to yourself and for all allies within 30ft of you.

Infinitum: In order for the body to withstand the power of the Infinitum, it will actively alter their body to become more sturdy, while attuned, it set the user's CON score to 20. While in rapier form, you can use a bonus action to cast a spell you have stored in the box's databank, without expending a spell slot or using any material, verbal or somatic components. Once used, this property can't be used again until the next dawn. 

Librarium: While in Box Form, you can open it and speak the command word to create a magical portal. When opened, the portal leads to a demiplane that appears to be an empty room 30 feet in each dimension, made of crystal. When the command word is spoken again, the portal disappears, and any creatures or objects inside the demiplane remain trapped there, as the box and the portal also disappear, the box reappears in your hands. Each time you speak the command word, you can create a portal connecting to the same demiplane created previously with the box or to the spot you once were before entering.

Proficiency with a Rapier allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Bonus: Magic, Bonus: Spell Attacks, Bonus: Spell Save DC, Advantage: Ability Checks, Set: Constitution Score, Ancient Technomiran Bladesinger, Finesse, Vex