Energy (also known as Ki, Mana, and others) is the physical phenomena manipulated to create movement, force, and matter. Different forms of energy are available depending on the parallel world; these forms also behave differently from each other and thus can be use in unique ways respective to its world. Energy present in one world would not appear or naturally occur in other parallels.
- Asadal: "Energy" is a physics-based quantitative property that is transferred to an object to perform work or to create heat in a conserved manner. It has two fundamental sub-forms: kinetic and potential; although there are several types such as mechanical, electrical, and thermal, among others. Unique to Asadal is the presence of Quantum energy which can be used to open wormholes for teleportation of mass across space and time - including through parallel worlds.
- Murim: "Ki" is a vital energy that can transformed by trained practitioners of martial arts into physical force. It can also be used for medicinal effects by trained healers using certain medicinal items possessing Ki or through techniques associated with martial arts. Ki is found and reproduced in all living beings and is expelled/radiated by them either unconsciously or consciously to the environment. The flowing ki can then be captured and used by other living beings much like the conservation of Asadal energy. Ki is sub-divided into its two fundamental types: Yin and Yang. Yin (dark/negative) is associated with the physical phenomena of coldness while Yang (light/positive) is with heat. Living beings must maintain a harmonious balance between their Yin and Yang energies which continuously consume/dominate each other; otherwise, they may suffer from health conditions. Some Murim martial artists however deliberately destroy their own balance to enable the use of specific Yin- or Yang-techniques but this requires great skill to be pulled off successfully and without harm. Ki can be cultivated through regular practice such as meditation. The fundamental concept of Murim martial arts is rooted in cultivating an individual's Ki to the highest potential.
- Fantasy: "Mana" is a free-flowing energy that is naturally reproduced from the environment. It is a classical element of aether or quintessence that is manipulated through magic to conjure or transform earth, water, air, and/or fire according to a specific command (derived from a magic spell) meeting the user's will.