As long as you manage to get on their backs and they don’t show off their gymnastics moves (barrel roll) you are good and keep stabbing it with your sword until it is dead. But I recommend having something to distract it too. My Parasaur (Yoo) and I were returning home from a failure trip trying to farm chitin for some armor. And we were passing by a swamp when I saw a lvl 40 sarco and I was like Huaaaaaaa, there is a noob here. And Yoo attacked it while the sarco was focused on killing Yoo I jumped on its back and managed to balance on it and killed it with my sword. Yoo didn’t die and I wasn’t even injured.

More Sarco Encountering Tips