Heart

Umasou is a small pink Ankylosaurus with an orange shell and red spikes and tail club.

Umasou is very cheerful and determined to be just as strong as his adoptive father Heart. He's also bold, like how he told Gonza he was well aware of what Heart really is, and did not care.

Found as a small egg by his adoptive mother, a kind, maternal Maiasaura as she was collecting berries by the riverbed, Heart was initially raised as a plant eater along with his adoptive brother, Light. When he was young, he mostly feasted on berries to survive, unable to sustain himself on acorns and leaves like his mother and brother could, a fact he resented. After it was exposed that he was a Big Jaw by Gonza and nearly giving into his predatory instincts, attacking his brother, he runs from his family and into the plains, eventually growing into a strong young Tyranosaurus. (Who he was raised by in that time frame is unknown.)

Later in the story, it is heavily implied that the egg that the Maiasaura found was none other than Baku's lost egg, making Heart Baku's biological son.

Heart told Tyrano to eat him in the 2018 Anime

Heart is something of a confused character that, despite being raised by a Maiasaura family, begins developing a taste for meat after eating part of Gonza's tail and even started to fall into predatory instincts.

When he first hatched after being brought in by a motherly Maiasaura, Heart came off as playful, enjoying playing with his brother but gets frustrated when he keeps losing at arm wrestle, and he is also timid and tends to cry a lot. He is insecure about his origins, especially his curiosity about enjoying biting on a lizard's tail, and cried when Light declared Heart to be a Big Jaw. When he saw a group of Big Jaws eating a Triceratops he became very frightened and ran off to warn his brother and mother. When Gonza declared Heart to be a Big Jaw and tried to make Heart eat his brother, Heart flew into rage and denied it before biting off a piece of Gonza's tail. Upon eating it, Heart realized Gonza was telling the truth and found meat delicious to him, he then ran off leaving his brother and mother.

Growing up, Heart trained himself to be an adept hunter through managing his strengths and weaknesses to become strong to survive, developing a fierce, tough, strong-will, and confident attitude. He defeated a herd of Titanosaurus by himself and ate one of them before running off when Gonza and his pack arrive, and mocked Gonza for his short tail. Heart is also very brave as he did not hesitate to take down Gonza and his group, and later fighting Baku despite the latter being much larger than him.

When he first met Umasou, he was going to eat him until the Ankylosaurus believed Heart was his father, leaving him baffled and confused, especially finding himself lecturing Umasou. At first thought, Heart thought of fattening him up and growing older to eat him but changes his mind when starting to feel attached to him. Heart started to become protective of his adoptive son as he protected Umasou from a Chilantaisaurus and became frantic when he ran off, prompting

He is a dark teal Tyrannosaurus with thin red streaks all over his body. His eyes are blue with a yellow sclera.

Name Heart Aliases Hato Family Baku (father) unnamed adoptive mother Light (adoptive brother) Umasou (adoptive son) unnamed adoptive brothers and sister Gender Male Likes Eating red berries, Umasou, Light, meat, Pero Pero, his mother, light DisLikes Umasou wandering off, Gonza, being a “Big Jaw”, nightmare of eating his mother and brother. Status Alive Species Tyrannosaurus Eye color Blue with yellow sclera