Vasu

Vasu is a jeweler from both Oracle of Ages and Oracle of Seasons. He facilitates most the services associated with Magic Rings, including appraisal and storage. His two pet snakes are used to transfer rings from one game to another. His shop can be found around Horon Village in Oracle of Seasons, while Lynna City holds is residence in Oracle of Ages. Regardless, the shop looks almost identical in both games, both exterior and interior included.

Appraisal
Magic Rings with unknown properties can be brought to Vasu for appraisal, revealing the rings' true potential. The first appraisal in each game is free, but every subsequent appraisal costs a few rupees. If Link already possesses a ring identical to the one he just paid to be appraised, Vasu will offer to purchase it. It costs 20 rupees to appraise a new ring, but Link receives 30 rupees for rings he sells to Vasu.

All appraised rings are automatically held by Vasu, as Link can only carry a few depending on the size of his Ring Box. Link can return to the Magic Jeweler's shop to exchange rings in his box for ones Vasu is holding, or vice versa.

Ring Transfer and Fortunes
In front of the counter to either side of Vasu are his two pet snakes, the Red Snake and the Blue Snake. These snakes will allow Link to transfer all his appraised rings between linked Oracle of Ages and Oracle of Seasons files. The rings can be transferred in two ways:

With the Red Snake, Link can transfer his rings via Ring Secret. By talking to the Red Snake in one game, he can receive a "secret" in the form of a 15-character password. This password can then be told to the Red Snake in the opposite game, where Link wishes to have his rings transferred. If done correctly, all of Link's appraised rings from the opposite game will appear in the other game's ring list. Rings can only been transferred between two linked game files. Otherwise, the Red Snake will not accept the secret.

With the Blue Snake, Link can transfer his rings via Ring Link. Two Game Boy Colors can be connected by a Game Link Cable. By connecting Oracle of Ages and Oracle of Seasons in this manner, then talking to the Blue Snake and selecting "Link", a Ring Link can be performed, and thus Link's Magic Rings will be transfered without the use of a password. As with the Red Snake, Ring Links will only work between two linked game files.

The Blue Snake also has a second purpose, which is telling "Ring Fortunes". By connecting Oracle of Ages and Seasons with a Game Link cable, then simultaneously speaking to the Blue Snake in both games, a Ring Fortune is performed. Ring Fortunes give both games a new Magic Ring to be appraised, as a sign of "friendship". No rings can be obtained exclusively through this method, therefore Ring Fortunes are not required to obtain all the Magic Rings. Ring Fortunes can be performed with any two Oracle of Ages and Oracle of Seasons game files, although they cannot be performed with two identical games (two Ages or two ''Seasons).

Ring Link and Ring Fortunes can only be used on Game Boy Colors, and not Game Boy Advances.

Trivia

 * As a character, Vasu might have been inspired from Hindu Deities of the same name, if only due to namesake and his South Asian style.
 * The only difference between Vasu's shop in both games is the sign of a ring seen in front of the shop, which is red in Oracle of Seasons and blue in Oracle of Ages.
 * In Orace of Seasons, the roof of Vasu Jewelers will also change change with the seasons. It is light green in Spring, dark green in the Summer, ruddy in Autumn, and blue in Winter.
 * Opposed to every other character appearing in both Oracle games, in a Linked Game Vasu doesn't recognise Link and oddly presents himself like if they never met. This is probably due to meeting him not being needed to finish the first game.