If you are on a pvp server(pve works as well), and you're raiding someone, try to use the rhino's charge attack. If your opponent has a rex, and you hit it with a full charge meter, it will be an instakill.
When KOing just run in circles filling it with tranq arrows or darts(high level) this is the way to cheese this Dino’s taming. Even someone that just got into a world with good movement speed could do it easy. And the Dino’s are super op when fully charged. This will help ALOT :)