The author's style of writing in the passage you provided is descriptive and suspenseful. He uses vivid language to paint a picture of the scene in the reader's mind, and he builds suspense by describing the falcon's attack and the raven's defense in detail.
The author also uses personification to give the animals human qualities. For example, he describes the falcons as being "in a heat of fury" and the raven as flying "unconcernedly." This personification helps the reader to relate to the animals and feel more engaged in the story.
Overall, I think the author's writing style is very effective. He is able to create a clear and vivid picture of the scene in the reader's mind, and he builds suspense in a way that keeps the reader engaged.
As for whether his story is a success or a failure, I think it depends on what the author was trying to achieve. If he was trying to write a story that is descriptive and suspenseful, then I think he has succeeded. However, if he was trying to write a story with a clear plot and resolution, then I think he has failed. The story ends abruptly with the raven flying away, and the reader is left wondering what happens next.
Overall, I think the author's writing style is very good, but his story could have been improved with a more clearly defined plot and resolution.