Kaio-ken Kamehameha

The Kaio-ken Kamehameha is exactly what it sounds like: Goku activates the Kaio-ken to multiply his power, then channels that amplified energy into a Kamehameha wave. The result is a beam significantly larger and more powerful than either technique would produce on its own. Visually, it resembles a standard Kamehameha but with the user cloaked in the Kaio-ken's signature red aura, and the beam itself takes on a deeper, more intense quality as the multiplier increases.

The combination is particularly dangerous because the Kaio-ken's strain compounds with the energy expenditure of the Kamehameha. Firing a high-multiplier Kaio-ken Kamehameha leaves Goku's body in a state of extreme exhaustion and pain, making it a true last-resort technique in most situations.

The technique's most legendary use came during the Saiyan Saga. After Goku battered Vegeta with a Kaio-ken times three physical assault, the Saiyan prince snapped. Vegeta launched himself into the air and fired his Earth-Splitting Galick Gun straight down, declaring he would destroy Goku and the entire planet with one shot. Goku had no choice but to meet the beam head-on with a Kaio-ken times three Kamehameha.

The two beams collided in one of Dragon Ball's first great energy clashes. When the blasts proved evenly matched, Goku surged to Kaio-ken times four, and the Kamehameha ripped through the Galick Gun, launching Vegeta into the atmosphere. Goku's body was left devastated by the strain, but the Earth survived. Vegeta's stunned reaction, realizing someone's beam could match and overpower his own, was a turning point in the rivalry.

Against Frieza on Namek, Goku fired the Kaio-ken Kamehameha at its peak: times twenty. After a vision of his loved ones being killed drove him to push past all limits, Goku pummeled Frieza and then unleashed the massive beam. Frieza blocked it with one hand, then took the full force of the blast. Despite showing visible damage, the tyrant was barely hurt. The technique's failure against Frieza at full power drove home that the Kaio-ken had limits even the Kamehameha could not overcome, foreshadowing the need for Super Saiyan.

In Dragon Ball Super, the combination returned in spectacular fashion as the 10x God Kamehameha. Using Super Saiyan Blue Kaio-ken against Hit during the Tournament of Destroyers, Goku fired a God Kamehameha so powerful he rode inside the blast itself, attempting to punch through Hit's Time-Skip. It marked the Kaio-ken Kamehameha's evolution from a desperation move into a divine-level finishing technique.