Mazin Power (マジンパワー Majin Pawā) is a function utilized by the Mazinger line of robots throughout the series. Initially debuting as a one time use attack in Episode 29 of the original Mazinger Z television series, it went on to make further appearances in the Super Robot Wars series as a passive ability.
By disabling it's limiters and charging up energy, the machine can release all of this energy at once to increase the overall power of the machine beyond it's usual capabilities. This allows the machine to reach incredible levels of strength and energy, bolstering physical attacks and supercharging energy-based special attacks. These effects are temporary, however, and are usually followed by significant cool-down times to prevent overloading the machine.
Within the continuity of Shin Mazinger ZERO and its sequel, Mazin Power, using the kanji for Demon God instead of the standard katakana, serves a different purpose, being tied into the activation of the Seven Black Boxes that are tied into both Mazinger Z's weapons and abilities, as well as the awakening of Mazinger ZERO.