"Double Spin Attack"
In order to acquire this magical ring, Link must complete the Plen Secret. During a Linked game of Oracle of Seasons, a Golden Subrosian will appear within Lava Lake. Speak with this Subrosian and he will tell you a secret. This secret then can be told to Mayor Plen in Oracle of Ages. After telling the secret, the Mayor will reward Link with the Spin Ring.
When equipped, Link will be able to perform a double Spin Attack. Link can charge his Sword, just as he usually does, but upon releasing, Link will spin twice in a row. Considering the amount of damage a spin attack does, the double spin attack is a very useful attack against difficult enemies and bosses, including Ganon.