The Chakra System
To perform techniques, ninja need to use their chakra. Chakra comes from two places: (1) the body energy inherent in the trillions of their cells and (2) the mental & spiritual energy gained from exercise and experience. To perform a jutsu, the ninja will bring out and release these two energies. The amount of chakra required for a technique will vary depending upon its size and complexity. Each ninja has the potential to better utilize an elemental Ninjutsu style.
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For Taijutsu the ninja does not need to necessarily use chakra, as some attacks merely use the stamina required to carry out the attack. For Ninjutsu the ninja's chakra control will determine how much chakra is used on the technique. For ninja with excellent chakra control, they will use the minimum amount with nothing wasted. For ninja with poor chakra control, they will expend more chakra than needed to accomplish their jutsu.
