Rings are a variety of items featured in both Oracle of Seasons and Oracle of Ages. They provide a multitude of different effects, from turning Link into a Moblin to adding higher damage multipliers to his blade and more. However, before such effects can take place, Link must get them appraised at Vasu Jewelers so they become Magical Rings.
Rings can be obtained in an array of manners. The most common way of receiving rings is through chests, whether in dungeons or out in the fields. Another method is via Gasha Nuts, which can be "farmed" in the sense that Link can plant multiple Gasha Seeds, zone a few times, then reap the rewards in no time flat. There are many rare situations where Link can purchase rings, although they are at assorted prices.