assimilation

you take two objects or items and suck the magic out of them and imbue it into your body. you take any bonuses as well from the items. leaving them empty and drained of all their magic.

you can only use said spell on objects of any rarity below legendary.

to assimilate objects higher, you need two other casters to give you their ninth level spell slot. 

for objects that have a soul or are filled with sentience. you can either leave them in the item or allow them into your mind. the only upside is that they can concentrate on spells for you.