Phlogiston

Phlogiston is the raw material of which gods, ghosts, and dreams are made. It is created by the Astral Plane. Phlogiston is chemically inert and electrically neutral. It has inertia but no mass until shaped. Phlogiston separated from the construct will dissolve into nothingness in a few seconds. It can be shaped into matter or energy, and acts according to the whims of the user no matter how contradictory that may be to the actual rules of physics in the real world. The more complex and hardy the construct, the more energy is required to sustain it. A ghost is barely capable of interacting with the real world, whereas a godling walks, breathes, and bleeds from his wounds.