After inheriting the Embryo, Es used most of its power to create the World of the Tsukuyomi to act as a buffer between the Boundary and the XBlaze world. As long as the Embryo remained within it, the Tsukuyomi would stop seithr leaking out of the cauldrons to flood the world and the Black Beast would remain trapped in the Boundary. However, when Es released her memories to escape the despair of watching Freaks kill her loved ones, the memories became Memory Fragments and the World of the Tsukuyomi was transformed into the Phantom Field.
The concept of time does not exist within the Phantom Field. Possibly as a result of this, anyone inside the Phantom Field does not need to eat. Inside the Phantom Field it is impossible to use offensive magic. Those who enter the Phantom Field forgets their name and will eventually lose all of their memories if they are not given a new one. Additionally, the Phantom Field is filled with Memory Fragments that contain the memories of those who enter the Phantom Field and those close to them.
The Phantom Field is divided into several floors with barriers in between them. In order to travel between floors, one must collect Memory Fragments to pass through the barriers. Moving between the floors will cause the traveler to view the memories they have collected.
A mysterious world that exists in an alternate dimension. Strangely, the memories of others appear here in a crystalline form. It seems to consist of a number of different levels 
- XBlaze Lost: Memories, TIPS, #17