Estimating that many would have some trouble in understanding the partially complicated concepts of my story, I will explain most of the basics here. Please send requests if there is anything too hard to understand or something missing.
To start, the universe in which Core Planet dwells. It can be interpreted as our own universe, or another in a different dimension. And, with everything being fictional, I would at least suggest that Earth, the planet where the humans live in my story, is not the real Earth but at least a planet that looks much like the real Earth, but is different in much ways. Core Planet is a planet that is completely isolated from other galaxies and solar systems, instead it dwells alone in space, illuminated by the Fourth Sun Aduran and having a moon orbiting around it. It is located relatively near Earth (the one of my story), that is located near the edge of a galaxy and protected by many planets, comets, meteor fields and icy zones against threats of all kinds, although there is a safe route that is known to the spaceships of Core Planet that have to travel to Earth for any reason.
The universe in which the fiction takes place also has the difference to the real one that there are more kinds of energies than there are in the normal universe, and they also have other characteristics. For example, fire can be converted into energy. In this form, its consistence is unstable, and it fades out quickly, much like other energies, but it also doesn't have to consume materials like wood to remain in the physical world. The fire energy can also be converted into normal fire. For example, creating a simple fireball into one's hand is a result of summoning energy and converting it into fire immediately to get a flame. As it is very unstable, the fireball will have to be fed continuously by small amounts of energy, or get some material to consume to remain in the physical world.
A living being can acquire the ability to create energy by mastering the ability to do so. Non-living objects and beings that do not master the ability necessary to create energy can only convert one energy into another, which is the reason that most beings have to breathe, eat and drink. The beings of Core Planet are able to create energy at different levels, which also defines their power level, while some of them, and the vast majority of the inhabitants of Asgard, are unable to. Therefore the beings of Core Planet have to consume less to live, how much is also dependant on their level. The ones that don't master the creation of energy must eat, drink, breathe and rest normally, according to their body, while the most powerful inhabitants of Core Planet can live without ever doing any of these, and sometimes even store additional energy into their bodies as they produce more than they consume.
There are three kinds of sources of which a living being having mastered the art to create energy can draw the power from: the body, the mind, and the soul. The average being of Core Planet is only able to use one of these sources on medium extent, which is not enough to allow it to live by itself, but it reduces the necessity of food, water, air, and rest by a lot. Some beings go further in the mastery of a single form of the sources, others master two or even all of them. These energies can also be used for fighting means: energy from the body source becomes Strength, the one from the mind becomes psychic power, and the one of the soul becomes Soul Power. The power sources can also be combined to second-grade combo energies: body and mind makes elemental power, mind and soul creates magic power. Finally, the three resulting energies as well as the second-grade combos can be combined into third-grade combos, which are very powerful:
-force and psychic power creates kinetic power control
-force and elemental power creates elemental physics
-psychic power and elemental power creates Enhanced Elemental Power
-psychic power and magic power creates Enhanced Magical Power
-Soul Power and Magic power creates Mana
-soul power and psychic power creates Spiritual Power
There is also the combination of the three powers - body, mind and soul -, but the resulting energy can not be created by anyone but M himself. It only exists in the Endless Ocean of Calm.
Next, the different energies that exist in the universe: The elemental ones (Fire (heat), water, ice (cold), nature, electric, light, magnetism, gravity, wind, earth), ghost, darkness, magic, soul, psychic, Mana, Time, Dimension, and Spiritual Power. There are also many other forms of energy, but these are the ones that are most known and used by the majority of beings. Other forms of energy, like Leviathan energy, are only used by few, and will therefore be mentioned in the sites of their respective users.
The elemental energies fire/heat, water, ice/cold, electric, magnetism and wind have got the same concept: they can be created out of elemental power or the element that they stand for, and are unstable. Each energy can replace the regular life power of a being, and if it is converted into the energy before being used it will also slightly change the user. For example, a being that masters the use of elemental power so that it uses fire energy to keep itself alive will progressively change into a fire elemental, going through different stades. By picking an elemental side, the being gains resistance towards the element it lives of (a fire being will take much less damage from fire), and eventually become totally immune to it like a fire elemental while also acquiring certain abilities, like breathing in and seeing through lava like a fish does in water. In exchange, the being will become weak to the counter element (with the example of fire/heat, it can burn through plants created by natural energy and thaw ice, but it is easily extinguished by water and wind). This evolution can be cancelled out by either feeding on all the energies together, making them compensate each other, or by using only energy that has not been converted.
Ghost energy is a subclass of soul energy, created by the dark part of a soul, or a ghost. It has no material which it can be converted into or from, and has no effect on the physical world. Instead it affects the spirit and mind of living beings, damaging them heavily already at low levels. Its destructive power being fully concentrated on the spirit, it is completely useless against physical non-living objects. The counters towards it are light, psychic power, soul power and dark energy.
Natural energy is a subclass of life energy, and basically the energy that allows one to grow. It also allows plants to live. Natural energy can be converted into plants and trees, has different powers when being used for destructive means, and has much more effect on those that use it. However, already a low-level mastery of natural energy is enough to live with. Natural energy can also be created as a combination of light, earth, and water energies.
Light energy is he opposite of dark energy, it cannot be converted into any material, it repels the darkness as well as other forms of energy, and can only be used by beings that have a certain degree of good in their souls. With the exception of dark energy, there is no effective counter towards it, which is one of the main reasons that it is so powerful. Mastering the light requires immense training and a good soul, but it is worthy, as light energy is an incredibly versatile power for both offensive and defensive purposes. The speed at which it works is also an incredible advantage.
Dark energy is the opposite of light, and one of the most useful powers. Mainly used by undead, it absorbs other forms of energy and can even return to its user to add to their energy. It can be converted into Dark Matter, which still has the characteristic of absorbing energies it comes into contact with. As opposed to dark energy, Dark Matter is able to absorb light energy of any kind while it is a question of power if dark energy gets destroyed by light energy, or if it absorbs it into it. Light energy having the advantage of power on its side, only a dark attack of at least three times the power of the light energy it is sent against can effectively absorb it, while Dark Matter can absorb light energy of almost every degree of power while being relatively limited with other forms of energy. Dark energy can only be used by someone or something that possesses a minimal degree of evil in their soul.
Magic and Mana powers are very similar in most ways, but also differ in others: magic power is the kind of power that can be used by a being having a free will and enough willpower to shape that will into something. The effects of magic are classified into three sectors: creation, manipulation, and destruction. Creation being the sector whose use usually drains most of the user's life power, it is only used by few. Manipulation is slightly different, as it involves many things such as moving something around, changing its shape or turning it into something completely different. Changing the object requires a lot of energy much like the creation powers, but it is still less since the materials are already present, while other powers depend much on the case. As a basic rule, it can be said that doing something with magic power requires the same amount of energy as it would do by doing the same thing physically, although true masters of soul and mind power do not have a problem with that. Using magic power requires a certain vocabulary that is like an order or a name of the action that has to be taken. For example, if someone would want to turn stone into gold, he either could order that stone to change its nature ("Stone, turn into gold!") or say the name of that spell ("Hand of Midas!"). Mana is slightly different, as it requires much less willpower and intelligence in general, making it able to be applied by beings that have a soul and the intelligence level of an animal. It can also be used by beings with more intelligence and willpower, but is generally less precise than magic. In exchange it is much safer to use Mana as magic power can have a completely different and possibly lethal output if used wrong, while that can't happen when using Mana: a magic process can kill the user if it was formulated wrong, draining all of his energy as the power is external, but Mana only works through the user and can be interrupted, but the output of magical powers is generally more precise. Mages and Wizards are therefore introduced to Mana before learning about magic power, while at the same time learning the vocabulary and rules of magic. This way, they start with something that has close to no risk and is also less dangerous for others, before proceeding to the more complicated and subtle magic. Mastering both Mana and magic is hard, but it allows a wizard to attack a foe with fast techniques (Mana) to avoid being caught offguard while concentrating on casting a spell (magic) if the foe is at a distance and could block the raw hits of power cated by Mana power.