Kaioken

This is a technique which its user can multiply their power level. This can multiply power and speed. During the Saiyan Saga, King Kai teaches Goku this technique. If you use this technique recklessly, it can put a strain on your body. Blue Kaioken is when Goku added the Kaioken on top of Super Saiyan Blue. Goku originally used the Kaioken against Vegeta. Goku originally planned to use Blue Kaioken against Beerus, but then he used it against Hit.