They spawn in the snow biome and always spawn with 3 Carnos as allies if your on a tame it can make the tame go out of control and you won't be able to control it affects almost all dinos when tamed you can Ally wild Carnos for a short period of time but the roar if used to much will put your Dino to sleep
It's roar usually makes your dino scared and flees with you in no control. BUT I once have only been hit by a bit of the roar and only felt a bit scared and I was still I'm control. Proctodons, flyers, baryonyx is the best I suggest for escaping this wild beast. Goodluck survivors!
First day it was released, started a new character made a stone house boat and headed north. Was docked, taming a direwolf. Suddenly it drops from a cliff with 3 carnos. They surrounded my boat and wiped me in three minutes. If you see the buff, gtfo.