This sound effect can be found on Soundelux Sound Effects Library, which was made by SoundDogs. It’s Hollywoodedge, Bear Grizzly Roar Sin AT030301 in various slowed down pitches. The last growl has a standalone sound effect on SFX Kit as Sound Ideas, MONSTERS & CREATURES \ BEASTS - EXTRA LARGE MONSTER: ROCK BEAST: GROWL 06. The third growl is same as SoundDogs, Monsters, Gorilla - Bear Growl Low Long Sweetener Single Gorilla Vocal.