When finding these things as a beginner. You are dead if you go too close to it. If you have a trike and you really fudging wanna kill them or they are causing too much problem, Attack it with a trike. Triceratops have knock back when hitting creatures, but you can spam the trikes attack knocking those theris back, it also damages theris. It means that if you have a trike, use it. Its a fixed-in-place Battering ram that doesnt get damaged because of knock back damage.