One is a challenge,
Two is deadly,
Three is a nightmare,
Four is lethal,
Five is a demon,
Six is terrifying,
Seven is a suicide mission,
Eight is a cult,
Nine is a giga killing squad,
Ten is Satan himself.

Useful tip, don't lead the allosaurus' into another pack. Right now there is a pack of 15 allosaurus' out the front of my base.

They say beaches are low resource/low threat areas right? WRONG! I used to live in one close to a cold region and some of those decided to run around the beach killing everything there. Fine, I hid from them in my tatch base and once they were far enough I thought I was safe, that until another freaking pack started doing the same. I hid my Dilo (Galinha Punk, my beloved only tame, great companion) inside the base and ran through the ocean to hide on some stones. And this was way before they cold spot me. Result: I had to hold my tears and watch in horror as they destroyed the little base I put on all my effort to build, killed my poor boy and kept going like it was nothing! Their levels were way too high, I couldn't fight them, but I was so sad I tried, died, couldn't respawn there cause I had no bed anymore, and couldn't get my stuff because they were near. Of course i waited until they went away, and of course wild dilos destroyed the rest of my stuff. I shall have my revenge!

Mainly they are in the forests or in the redwoods killing other creatures or walking around.