In JACK, Jack and other various characters throughout the game utilize Mana to cast magical spells. In the game, each character has a Mana bar that slowly recharges over time. Some items recharge the bar, and each character has a stat that determines the recharge time of the bar. Each spell drains some of the bar when it is cast, and other actions, such as binding with a Familiar, uses up Mana as well.
Mana is also very important to the lore and story of the game. The benevolent dragon who created the dimension, Kyggzo, also created Mana to hold the universe together. Each of his scales is ripe with Mana, and he himself is thus the strongest magic user in the game. At the center of the universe is a magical tree made of pure Mana called the Life Sprout, whose branches keep all of reality together using Mana. However, when the scales of Kyggzo are stolen from the Life Sprout, it begins to wither, starting Jack's quest to find each and every scale.
The Last Valkyrie
In this game, Mana is called Spirit. Spirit is again described as the energy that holds the world together. It is also described as the energy that allows living things to continue living, and that their spirit energy contains their memories. When a living being dies, its spirit energy is sent to the Underworld to continue on as an undead spirit. The plot of the game, however, involves the ruler of the Underworld, Helreginn, accidentally allows the spirit energy from the Underworld to seap back into the realm of the living. This is catastrophic as it allows horrible monsters to form and terrible machinery powered by spirit energy to be produced. The chaos caused by this act leads to total global destruction and multiple horrible wars, which only generates more and more spirit energy.
As a Valkyrie, Ellie Rinne is tasked with hunting down spirits and taking their Spirit energy back from them, returning it to the Underworld where it belongs. Spirit energy is also an important part of the gameplay, as all supernatural beings have a certain amount of Spirit energy; when Ellie or her friends use specific attacks, they drain a little bit of that energy into themselves, weakening their opponents and powering them up. The more spirit energy a character has, the more powerful they are. Additionally, they can expend some of their spirit energy to use ultra-powerful Soul Wretches, creating massive amounts of destruction. Additionally, draining Spirit is integral to gathering Essense.