Dragon Ball Z Episode 18 -

: Upon landing on the tiny, high-gravity planet, Goku famously mistakes Bubbles the monkey for the legendary King Kai.

You can find this episode and detailed guides on official and community sites like: Dragon Ball Z Episode 18

: Gohan transforms into a Great Ape (Ōzaru) for the second time. To stop the rampage, Piccolo destroys the spacecraft, which ends the holographic moon and causes Gohan to return to normal. Where to Watch : Upon landing on the tiny, high-gravity planet,