The Kaioken technique, which Goku learned on King Kai’s planet during the Saiyan Arc, allowed the user to multiply their power levels a number of times over depending on how strong they are.

Kaioken, of course, first appeared in the Saiyan Saga of the Dragon Ball Z franchise, with Goku learning it on King Kai’s planet following his death to his brother Raditz. The “Fist of the ...