Mr. Thicknose is the (former) secondary antagonist turned supporting protagonist of The Land Before Time VIII: The Big Freeze and a supporting protagonist in The Land Before Time TV show. He is voiced by the late Robert Guillaume in the movie, who also voiced Rafiki from Disney's The Lion King, and Dorian Harewood in the TV series.
Mr. Thicknose can be a bit gruff in the film In the film until the climax.
Since Mr. Thicknose is a full-grown dinosaur, he seems to hate kids like Littlefoot and his friends, but at the end of the film, he no longer hates kids.
In the TV series, he is often kind-hearted.