Ranger Rex is a very serious and strict person. As Ranger Rhino can get quite angry when their workers fail to do a job, Ranger Rex can be twice as worse. In "Let's Get Tiny", he even fired Ranger Rhino after Banana sabotaged his monthly cabin inspection. He then replaced Rhino with a new ranger named Ranger Slothbones, a very lazy individual who was later fired after being blamed to cause the shrimp vortex, also caused by Banana.
Ranger Rex is a Tyrannosaurus Rex. He is a bit taller than Ranger Rhino. He has brownish-green scales and dark yellow eyes with black circles around them. He wears a beige shirt and hat with a black trim, and he wears dark green cargo shorts. His outfit is similar to Ranger Rhino's.