Nen is one of the defining features of the manga Hunter X Hunter by YoshiroTogashi. It is a technique that allows a living being to use and manipulate their own life energy (known as aura). The term "Nen" can also be used in conversation to refer to aura. A person capable of utilizing Nen is colloquially referred to as a "Nen user, while those who cannot go by the name of "non-users". Because one can craft a great variety of para-psychological abilities through Nen, it is considered a dangerous power that is kept hidden from the public at large to maintain balance in society.
The nature of Almighty Magic at it core is very similar and should be understood in the same way as the concept of Metapotence (simplistic conception of Omnipotence) as both powers allow the user to achieve anything and everything without any limit, no matter how impossible or contradictory with an metapotent’s explanation in doing this simply because it can while an Almighty Magic user’s explanation in being able to do this because it’s what magic for the most part is.