Mana

Possibly the most important aspect of any fantasy universe, mana, also known by names such as chakra, spirit energy or reishi, and aura, but also called by many others, is a difficult force to describe. It can best be caled the underlying life force that flows through any one being, or, in the case of Nobodies, one nonbeing, but few know of its existence and fewer still can use it, save in certain universes. In Kingdom Hearts, it can be said that it is mana that gives the Keyblade, and therefore Kingdom Hearts, their power, and is what allows Nobodies, the Heartless and the protgonists to utilize magic and Organization XIII to wield their respective elements. It can be seen that in any extraordinary universe, Kingdom Hearts or not, that mana is a powerful substance that many vie for control of.

Uses of Mana
Mana as a physical substance has many different uses. In Naruto, for example, mana is known by the name chakra amd is used by the ninjas and samurai that dwell in that universe to perform ninjutsu, genjutsu and, in certain cases, to be used in pure form as a weapon. In the Bleach series, mana is called reishi (or spirit energy) and is used in physical form to perform attacks, such as a Cero or Ichigo Kurosaki's Getsuga Tensho. Reishi in Bleach also often is allowed to leak out of the user, causing a phenomina known as spiritual pressure that is a direct measure of the user's strength and can be used to intimidate opponents. In many unskilled or very high-powered cases, spiritual pressure cannot be controlled.

In Kingdom Hearts, mana is used in increasingly diverse ways. Sora and other protagonists use mana to launch spells, perform limits or limit breaks, heal themselves, execute daring acrobatic maneuvers, or even just attack normally, in the case of the Explosion or Guard Break abilities. In recent spin-offs of the Kingdom Hearts universe that reveal similar event chains, characters have found themselves using mana in similar ways. One unique case in the universe of Kingdom Hearts Legacy, where La Lutte Pour Presque member Hanx wields a mysterious substance called Silicon, using his mana to bend and twist the grains to attack his enemies without any physical stimuli, in a similar fashion to the character Gaara from Naruto.

As more is revealed about the time continuems connected to Kingdom Hearts, and as other, different universes are revealed, mor about mana will undoubtedly be revealed.