DB Chapter 316
From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
"The Galaxy Strikes Back" (宇宙の恨み、フリーザを貫く！！, Uchū no Urami, Furīza o Tsuranuku!!; Literally meaning "The Hatred of the Universe, Pierces Freeza!!") is chapter 316 of the Dragon Ball manga.
Piccolo asks Goku if he's still not finished, and Goku says he needs a little more time. Freeza is really pissed at them now, when he suddenly gets blasted by... Kuririn and Gohan, with what little ki they had left. Freeza can't believe there's still more flies around, and yells that it all ends here. Goku says it's finally done, as Freeza begins creating a ball of energy. Goku launches the Genki-Dama, and it's gigantic. It comes down, and Freeza tries to hold it off, but it's way too big. The tremendous Genki-Dama drives Freeza down into the ground, and the impact creates a hole in the planet itself. Kaiō notices what's going on, and starts dancing for joy that Freeza's been defeated. There's a huge hole, surrounded by nothing but ocean, with water falling into the hole. Gohan and Kuririn surface and climb onto a rock, and wonder where Goku and Piccolo are.