Of the remaining four techniques Di Tou had an interest in, three were mixed, and one was red and outdated.
For the mixed ones, two of them were considered mixed because they used a special material that wasn't easy to obtain in modern days.
For example, one brute-forced the solution by using a material called Spatial Gold, which was an extremely strong material with Spatial connections. In this case, it could help stabilize space, connect it, and even directly 'seal' it inside of the ring if needed, although this was still far less efficient than simply stabilizing a space and connecting it to the Spatial Ring itself. Spatial Gold wasn't an extinct material, and in fact there were even a number of active mines on the five continents today, the only trouble was that a force occupied all of the known mines, and naturally any materials that flowed out would have an exorbitant price tag attached to them.
