Zol Ring

The Zol Ring is a ring-class item introduced in Golden Sun: Dark Dawn. It is equippable by all Adepts and increases agility by 80% (ie: multiplies by 1.8) when equipped. It can be first obtained in Passaj from the equipment shop as a gift from the smiths once you have placed the Sol Mask in the Alchemy Forge and re-ignited their furnaces. Later, multiple Zol Rings can be forged by giving Quality Zol to Obaba in Champa.

Analysis
The Zol Ring possesses the highest agility boost of any item as of Dark Dawn, almost doubling the agility of the character equipping it. Even the debilitating Safety Boots, which decrease agility by 30% (multiplies by 0.7) can't offset this boost, the net boost from stacking the two being a 26% boost. In addition, this is the only ring in Dark Dawn which players can obtain multiples of, so in order to give rings to each character one would have to use multiple Zol Rings.