Ball and Chain Trooper

A ball and chain trooper is ( as it's name suggests) a fully armored knight weilding a massive spiked ball on a chain. They appear as some of the hardest foes in several zelda games.

A Link to the Past
The Ball and Chain Trooper first appears in A Link to the Past as the guardian of Princess Zelda's cell. At this early stage of the game it is the most difficult enemy Link has yet faced; the weapon it is named for has a long reach and does serious damage. It also recovers fairly quickly from being stunned by the boomerang. Later in the game, when ascending the Castle Tower, Link must face several more of these foes.

Twilight Princess
The Ball and Chain Trooper also appears in the Snowpeak Ruins in the Twilight Princess. He seems to be reptillian and to kill him you will have to Clawshot over him when he throws his weapon at you so you can hit his tail.Or you could sidestep to avoid his attack and ues a back slice (secret skill) to get behind him. See also, Darkhammer

Minish Cap
These soldiers swing a damaging ball and chain, and are one of the hardest enemies in the game, but can be destroyed by:
 * 1) Dodging their ball and chains, then striking with your sword; or
 * 2) Using the Roc's Cape to jump over their ball and chain and perform a down thrust.

Quote from The Legend of Zelda: The Minish Cap Ball & Chain Soldier figurine: "Appears in the Palace of Winds and Dark Hyrule Castle. They're not fast, but that iron ball is a bruiser! Try to hit them after they swing the ball."