"Light of Justice, strike me! A weak god who cannot destroy evil is worthless!"
This technique is summoned when the user calls its name and raises up his/her arm. A few moments later, the energy storm will strike the user's hand, damaging the arm severely. While this is proven to be a self harming technique, those who survive it will gain immense power. There is also another variant in the game Dragon Ball Xenoverse 2. This variant is an energy wave fired from the eyes.
Fused Zamasu, after his face was scarred by Goku's God Kamehameha, calls upon the Light of Justice to spread his mutation to his arm - causing it to become larger, much more muscular and exposing his scarred flesh - but also increased Fused Zamasu's power. His aura also changes into a fusion of Future Zamasu's purple aura on the inside and the dark red outer part of Super Saiyan Rosé Goku Black's aura.
Video game appearances
This technique makes a debut in Dragon Ball Xenoverse 2 as two variations. The main version, like in the anime, was used to injure him into his Grotesque state. The Light of Justice also appears as a Super Attack exclusive to Fused Zamasu, allowing him to fire an electrical like energy wave out of his eyes.