Mr. Gus is a major character in Uncle Grandpa. He is a dinosaur man that protects Uncle Grandpa. He lives with Uncle Grandpa, Pizza Steve, and Giant Realistic Flying Tiger in the RV. He is very calm, unlike his friends, and is a very serious character. He is voiced by Kevin Michael Richardson.
Mr. Gus is a tall, green, scaly dinosaur man. He wears a white tank top, and no pants. He has a pink mouth, and a gap.
Mr. Gus is very nonchalant and laid back. He has a deep voice, and it's always monotonous. His expression never changes whether he is happy or surprised. He usually always has the same expression except for on occasions when he screams or his eyes go wide. Mr. Gus seems to be smarter then the rest of the crew, and the most level headed, though he is sometimes ignored like in the episode Funny Face when he told UG and Pizza Steve that they shouldn't make funny faces because they "cause a lot of pain". It is also revealed in Uncle Grandpa Sitter that his favorite Ice Cream flavor is 'Plain Vanilla'.
Mr. Gus is also very helpful and nice despite his appearance. He doesn't mind helping others, and he cares about others.
It is shown on numerous occasions that Mr. Gus sees through Pizza Steve's bragging and doesn't believe in it. He is usually who Pizza Steve throws the blame for him not being able to do what he claims he can, but Mr. Gus doesn't respond to this.
- Uncle Grandpa (Character) - Though they may not always see eye to eye, Mr. Gus is his friend and loyal body guard and is always there for his Uncle and Grandpa when he may need it the most. Mr. Gus constantly looks out for Uncle Grandpa's well being, even if it drives him nuts.
- Pizza Steve - They are friends and rivals. Pizza Steve's grandeur lies of achievements he's never earned and things he's never done get under Mr. Gus's skin, and Mr. Gus's serious and down to earth attitude seems to annoy Pizza Steve. Despite Pizza Steve rarely showing any regard for Mr. Gus's feelings, Mr. Gus does care about him and consider him a friend.
- Giant Realistic Flying Tiger - Mr. Gus seems quite fond of Giant Realistic Flying Tiger. She seems to return this affection namely by giving him tiny "kitty licks" on his face (mentioned in Tiger Trails and shown put in action in Bezt Frends. He also talks of her in high regard when asked about her and owns a pair of GRFT slippers that Uncle Grandpa gave to him as a gift.
- Belly Bag - Mr. Gus had helped and made sure Belly Bag was feeling better when he wasn't feeling so good in "Sick Bag", so Mr. Gus had given Belly Bag a pot of his Grandma's Chickendactyl Soup.
- He may actually be a human in a suit, in Tiger Trails, when the gang entered the nail salon, he says, "My nails have never looked better", showing a human hand out of his body, putting his reptilian hand back on afterwards. This might be untrue, though, as it would be near impossible for a human to live almost 2 billion years, or about half the time that the Earth has existed, without assistance from technology or a higher power.
- He made the cover of Non-verbal Weekly. A blue magazine that had his face on the cover.
- He sometimes has transparent eyelids because when he closes his eyes, his pupils show.
- Mr. Gus is most likely older than Uncle Grandpa, as shown in Jorts when he had a flash back to 1993,000,000 B.C.
- In the Jorts Title Card, he is wearing a button that has a picture of a pizza with a red prohibition sign over it.
- Mr. Gus works out by destroying cities, much similar to Godzilla, as shown in Mr. Gus Works Out. Since this city was inside the RV, it is possible the room he was in was a city simulator. Ironically, the same short aired shortly a few months before the 2014 Godzilla movie premiered in theaters.
- As revealed in Big in Japan, Mr. Gus is a great actor.
- As revealed in Slice of Life with Pizza Steve: Car Radio, Mr. Gus enjoys listening to classical music and thinks rock/metal music is garbage.
- "Belly Bros"
- "Tiger Trails"
- "Funny Face"
- "Moustache Cream"
- "Uncle Grandpa Sitter"
- Uncle Grandpa Ate My Homework!"
- "Uncle Grandpa for a Day"
- "Afraid of the Dark"
- "Treasure Map"
- "Locked Out"
- "Brain Game"
- "Mystery Noise"
- "Charlie Burgers"
- "Uncle Grandpa Shorts"
- "Big in Japan"
- "Leg Wrestle"
- "More Uncle Grandpa Shorts"
- "Viewer Special"
- "Bad Morning"
- "Prank Wars"
- "1992 Called"
- "Bezt Frends"
- "Food Truck"
- "Hide and Seek"
- "The History of Wrestling"
- "Sick Bag"
- "Aunt Grandma"
- "Slice of Life with Pizza Steve"
- "Tiger Talk"
- "Uncle Grandpa Changes a Light Bulb"
- "Tiny Miracle the Robot Boy"
- "Uncle Grandpa Sings the Classics" (Mentioned only in songs)
- "Mr. Gus's Work Out"
- "UG Rap Attack"
- "Board Game Night"
- "E-Mail the Duck"
- "Uncle Grandpa Cooks a Burrito"
- "Shave Time"
- "Moments in History with Mr. Gus"
- "Scary Cyborg Guy"
- "Can I get the latest edition of Non-Verbal Response Weekly? I made the cover again."
- "My name is Mr. Gus and I'm here to say, that he loves Peanut butter in a crazy way."
- "I thought the Uncle Grandpa RV was all set to drive itself."
- "Good morning."
- "What's up, kid?"
- "Danger Mountain? He's going to get himself killed!"
- "Who would have thought my nails could look so beautiful? Ssssshh"
- Hey Uncle Grandpa, we're on our way back we should be there in a few minutes. Pizza Steve has your cone. Is everything cool? Hey, what's all of that noise?"
- "This is not a treasure map, it's a stupid children's activity place mat!"
- "Stupid activity place mat for kids!"
- "The correct answer is...!"
- "You guys are weird!"
- "The answer is uhh... Spaghetti fish sandwich?"
- "Embrace the weird, Mr. Gus... Embrace the weird..."
- "Okay, you guys, that's Enough.
- "You didn't make that."