The sketch on the left is Yuji Horii, the main designer behind Dragon Quest, sending Toriyama a basic fantasy slime inspired by the western PC RPGs that he and his programmers were all into. Toriyama went "no, lets make it a funny little guy" and designed the iconic design on the right. With its memorable shape and face. And it became a series mascot that endures in Japan as one of the most iconic series mascots and printed Enix, and now Squarenix, a bajillion dollars.
https://thomaswell.medium.com/the-story-behind-dragon-quest-c914a7bd3d74 https://www.polygon.com/gaming/24094509/akira-toriyama-dragon-quest-slime https://xcancel.com/hamishsteele/status/1623436759215534080
All Toriyama ever wanted to do in life was draw cute lil blobby dudes
and by god he did it, even if it's not what he's best known for lmao
Goku started as a funny lil guy. He just grew into a big funny lil guy