Kaiō-ken times 20!!! (２０倍界王拳の賭け Nijūbai Kaiōken no Kake, lit. "The Risks of the Worlds' King's 20-Fold Fist") is the three hundred thirteenth chapter of the Dragon Ball manga.
Having been hit in the face with an elbow from Frieza, Goku is sent flying backwards. Frieza gives chase, but Goku regains his composure in midair and flies away, needing a quick break. He is upset about his current situation, while Frieza just grins. Frieza then attacks with a Death Wave, which leaves a long line of destruction in the planet. Goku is surprised at the attack's power, but Frieza says that he could destroy the planet with ease, as he did to Planet Vegeta. Goku reluctantly admits that he cannot win. Krillin hopes that Goku has a plan, but Piccolo says that he does not, and that Frieza is much stronger than they expected. However, Frieza says that destroying the planet would be anticlimactic.
On King Kai's Planet, Tien Shinhan cannot believe that Goku is getting beat while using Kaio-ken x10. King Kai also reveals that Frieza is only using 50% of his power. He says that this is why he told Goku not to fight Frieza, and that Goku has lost. Meanwhile, Goku realizes that he needs to use to Kaio-ken x20 to have a chance. As he powers up, he hopes that Frieza is bluffing, or he will not have a chance either way. Frieza is surprised to see Goku power up even more. After powering up, Goku charges towards Frieza and punches him in the face. As Frieza falls backwards, Goku chases after the tyrant and unleashes a Kamehameha. However, Frieza regains his composure and manages to defuse the wave. Goku is shocked to see that his attack has done nothing.