Eidolite, also referred to as Subatonium, is a dense collection of matter, which involves its quarks being pushed very close together. It is an artificially created matter, with no found natural counterparts in the universe. It is held together by the strong nuclear force, which allows for Eidolite to hold very tough, hard, and strong characteristics. With its dense nature, Eidolite is known to be very heavy. It is almost impossible to create as well, at least in high quantities. As a result, it has not seen many uses. Even with advances in technology, Eidolite has still been shown to be very elusive and valuable.
Lab-created Eidolite is incredibly easy to bend through strong force alteration fields, and responds to anyone's psychokinesis very easily. It typically takes a violet-ultraviolet glow, though it can be altered during the creation process in the labs. It tends to break down quickly when not kept carefully in lab conditions, appearing to crumble and diffuse into the air. Though typically solid, there have been rare cases where Eidolite has been created as a liquid.
The Eidolite made by powerful psychokinetics possesses many similar properties, such as its glow, hardness, and general texture, but there are many key differences. The least important of these is that each one seems to possess a signature color. For example, Moonmoon's Eidolite takes on a distinct royal blue hue. Psychokinetic Eidolite is also a lot more stable in uncontrolled conditions, as it slowly dissolves over a few minutes without concentration on the part of the creator. In addition to this, the Eidolite seems to respond almost exclusively to the psychokinetic influence of its creator, and it loses integrity when manipulated by psychokinetics other than the creator.