the yuty has two kinds of roars.

one of the roars can be used to buff your dinosaurs up.

whilst the other roar is used to make almost every creature run in fear.

if you use the buffing roar a good amount, your dinosaurs charge will remain for a long time.

and if you fill up the fear bar for the second roar on your opponent, they will begin running away

Giganotosaurus, Rexs, Spinos, Wyverns, Alpha Predators, Water Creatures, and Brontos are immune to the yutyrannus's fear roar

-ilovescugs