He is a light green or brown fish with glasses and facial hair. He wears a cream-colored hat with a cream-colored shirt and black boots as well. He's very short.
When SpongeBob finds him in the game, he tells SpongeBob random facts about jellyfish and asks SpongeBob to get him a solar radar that helps him figure out more about jellyfish. To get the solar radar, you have to get a pearl from a clam and swap it for the solar radar with Mack Mackerel. Then trade the solar radar for a battery with the biologist.
He appears as an explorer in the temple of the focusing orb. He tells SpongeBob all about the dangers that await SpongeBob. He tells him about the Corridors of Confusion, the Pool of Perception and the Doors of Deception.
He reveals that jellyfish are aliens looking for a secret portal (which SpongeBob finds and goes into during the game) located in Jellyfish Fields.
SpongeBob suspects that he made up the names of the obstacles in the temple.
He offers SpongeBob his flashlight (he uses them to look under the Hotel Deep Six).