Sherman Yang

Sherman belongs to Ares' cabin and is a son of Ares.

The Demigod Files
When Clarisse mentions that her brothers are messing with her in Percy Jackson and the Stolen Chariot, Percy instantly thinks of Sherman and Mark, which possibly means they are the most troublesome.

The Last Olympian
Sherman was one of the Ares cabin that was convinced by disguised Silena Beauregard to join the rest of the Campers in New York City in the battle against Kronos and his monsters.

Powers

 * Sherman has been trained in hand-to-hand combat at Camp Half-Blood.
 * He is very strong and swift.
 * He may have some small degree of powers that Ares himself possesses.
 * Being a child of Ares would make him an expert in all weapon usage and may even have some degree of magical control over them.