Big Alligator is a large male alligator with a muscular build and kale skin. He has tall, pink hair that looks like a Mohawk, and his eyes have yellow sclera and dark green eyelids. He also appears to have a prosthetic mandible made of metal.
He wears a big light blue tank top, dark blue pants, and a black belt around his waist.
In "Plaza Prom", he has slicked-back hair and wears a sleeveless black suit, a yellow tie, and a corsage.
- Big Alligator, like the rest of the Lizard Gang (excluding Chameleon Jr.), was designed by revisionist and storyboard artist, Anna Craig.
- In "We've Got Fleas", Big Alligator is seen with the Lizard Gang being members of the unnamed Human-based subculture.