In this task, you're given a story (which contains five sentences only). Your task is to find all the characters which are available in the given story.
Q: Sentence1: Bob was always beaten by his brother at chess. Sentence2: He decided to enlist the help of a local chess champion. Sentence3: Bob studied very hard. Sentence4: He challenged his brother to a match. Sentence5: He finally came out victorious.
A:
Bob, Chess champion, Brother