- “When this intimidating athlete is cut down to size, he'll adjust to being the supporting player instead of the star, and discover his strength isn't his most powerful weapon.”
- —Jumanji movie website
He is the avatar of Anthony Johnson.
- Zoology: He is an expert on animal behavior and biology, giving helpful advice and knowledge on the various creatures of Jumanji. He was even able to tame an Elephant to give him a ride.
- Weapons Valet: He carries a variety of weapons in his bag and gives them to Bravestone whenever he needs it.
- Cake: Consuming cake causes him to explode.
- Speed: He is a slow runner, possibly due to his backpack being loaded with weapons or because he's short.
- Strength: He was not strong when he slapped Bravestone in the face.
Franklin "Mouse" Finbar is one of four playable avatars in the official site's Rhino Run game. He must escape Jumanji by running through fixed routes of randomised hazards and collect gems by pressing the keyboard arrows or touch screen to move left or right. The more levels the avatar progresses through, the faster the speed will become and hazards will be harder to avoid. Collecting Mouse's pic-axe powerups will enable him to ride an Elephant for a brief period and render him invincible.
- Fridge initially chose Finbar as he misread his nickname as "Moose" thinking this would mean he is big and bad ass. He was shocked to discover he was short and he was actually called "Mouse."
- At first, when Finbar (Fridge) ate the pound cake at the Bazaar, he assumed his weakness of it was simply an addiction for it or an allergic reaction, only to then, a few moments later, explode.