Many of the urns surrounding the ring will release homing projectiles if broken. Additionally, a mage skeleton that throws the same type of projectiles guards the area and may break some unwanted urns with its own attacks. One of the urns is sitting on a pressure plate that will activate a trap of fire bolts if broken.
To easily claim the ring, start by disposing of the skeleton and then take a bow or any other kind of precise ranged attack. Identify the urn sitting on the pressure plate, shoot it from afar and use the nearby columns to take cover. The bolts shot by the trap will destroy most urns around the ring and all released projectiles will vanish once they hit a wall.
Increases Dexterity by 3 and obscures the wearer while rolling.