“After a young buffalo witnesses his mother’s torture and death at the hands of Native Americans, he will have to discover the true meaning of courage before he transforms into what he fears most.”

"discovering courage" is not something I can see. What is the visual metaphor you're going to use here? What does "discovering courage" look like?

You need to be crystal clear about his goal once his mother dies, what is trying to stop him from achieving that goal, and what is at stake if he fails.

Thanks for the feedback guys. I'm going to take the advice into consideration and post another version of this concept.

What Richiev said about "true meaning of courage". Obviously, to merely survive, he'll have to be courageous. It almost goes without needing to be said. And it's a subjective issue. But a log line is supposed to be about an objective goal or necessity. What is it?

Further, I suggest phrasing the inciting incident along the lines of "After his mother is killed by poachers..." and leave it that. The buffalo is a revered animal in the culture and tribal religions of the Plain tribes-- you're stirring up a hornet's nest by saying they would torture one. I don't think it's prudent to toss it into a log line without explanation or context. If the story pivots on the mother being tortured by Native Americans, lay out in the story -- but not in the log line.