What talent did Curley have in the book Of Mice and Men?

Curley's talent is as a fairly good amateur boxer. In Chapter 2, after Curley has made an appearance and behaved in his usual hostile manner, Candy tells George:

"That's the boss's son....Curley's pretty handy. He done quite a bit in the ring. He's a lightweight, and he's handy."

The reader will later see a demonstration of Curley's boxing proficiency when he attacks Lennie in Chapter 3.

Curley was balanced and poised. He slashed at Lennie with his left, and then slashed down his nose with a right....[Lennie] backed until he was against the wall, and Curley followed, slugging him in the face.

We can see that Curley has an inferiority because of his small size. Like a number of such small men, he has made the most of his body. No doubt he lifts weights as well as working out in the ring at the gym. His inferiority complex would explain why he married a girl who is apparently only about sixteen years old. He may feel inadequate to relate to a mature woman. It would also explain his bad temper and his aggressiveness. Candy understands him pretty well.

"Curley's like a lot of little guys. He hates big guys. He's alla time picking scraps with big guys. Kind of like he's mad at 'em because he ain't a big guy. You seen little guys like that, ain't you? Always scrappy?"

Curley's "scrappiness" will explain why he is so anxious to kill Lennie in the most painful way towards the end of the book. Lennie crushed Curley's hand after taking a lot of undeserved punishment. Curley wants revenge. Lennie has put an end to the little man's career as an amateur boxer. In fact, he might never be able to fight with anyone again, either in or out of the ring. Curley's wife will be somewhat attracted to Lennie just because she hates her husband and knows it was Lennie who crushed Curley's hand in their bunkhouse fight. This will explain why she stays to talk to Lennie in the barn and invites him to stroke her soft hair. And stroking her hair arouses Lennie, leading to his accidentally killing her when she starts struggling and trying to scream for help. Eventually this will lead to George shooting Lennie at the riverside and bringing the story to an abrupt end.

All of these events are examples of Steinbeck's "naturalistic" style. There does not seem to be a real plot. Things just happen, and one thing is the result of another. For example, when Carlson shoots Candy's old dog, George sees the gun, sees where Carlson keeps it, and sees how the complicated German Luger works. Carlson tells Candy exactly where he will point the Luger at the back of the old dog's head in order to kill it with a single painless shot. Later George will know exactly where to shoot Lennie in the back of the head with the same stolen Luger.