Nameless Book of Spells is a powerful grimoire from the age of the Eight Greed Kings.
During the era of the Eight Greed Kings, legends has it that the Kings possessed numerous objects of power that allowed them to rule the New World. The greatest in their magical arsenal was the Nameless Book of Spells. Worth a country's ransom, this tome is protected by strong magic, preventing anyone from touching it other than its rightful owner.
According to Evileye, it is a magic item that holds untold power known to a very few like herself. Through unknown magic, it was said that all magic spells of the New World is recorded in the grimoire and possibly even newly created magic spells gets automatically transcribed in its pages. It is unknown what kind of magic it is capable of, but its existence served as an example for the existence of the legendary 10th Tier Magic.
Based on the Web Novel, in that grimiore, there are records of spells up to the 10th tier. In fact, everything until the 11th tier or otherwise known as Super-Tier Magic by YGGDRASIL standard is recorded. Evileye stated that there is only one of the 11th tier was recorded in the grimiore. She even heard heard rumors about there being more than only one of such spells. In her own words, there might be other 11th tier spells that were not found or recorded yet.