The Gecko Monster is a Corrupted Gem that Steven Universe had to find and capture by himself on his first solo-mission. While Steven had to get it, it was Quetzalcoatl who poofed it for him.
Appearance[]
It is a long, slim Corrupted Gem with a snake-like body, a head and feet like that of a Gecko, and limbs tucked under its body rather than sprawled out to its sides like a real lizard.