The Legend of Zelda: Oracle of Seasons/Golden Monsters

The Golden Sage
It is said that a mysterious gold-cloaked sage resides somewhere in Holodrum, and has made the monsters appear. He eagerly awaits a person worthy of his treasure, and knows when each of his monsters have been slain. If you feel up to his challenge, then it's time to hunt the Golden Beasts!
 * Location: North Horon
 * Season: summer (chapter 3)

Just north of Horon village, go to the nearby tree stump and change the season to summer. Then go all the way west to the island where the first dungeon was. Go south (instead of going in the dungeon) and enter the small cave: the Golden Sage will give you the quest!

Golden Octorok

 * Location: Spool Swamp (chapter 3)
 * Season: summer

Enter the far southwestern corner of Spool Swamp to find the first Golden Beast, the Golden Octorok, an Octorok that shoots chunks of pure gold. This one will be rather tricky to defeat, because you can't knock it down a hole. Instead, you must tackle it the hard way with your sword.

Golden Moblin



 * Location: Woods of Winter
 * Season: autumn (chapter 5)

Head back over to the entrance of Snakes Remains and change the season to autumn (if you don't have the flippers, you must enter Snakes Remains to make it autumn). You'll find a Moblin has appeared, except he's gold! He is one of the four Golden Beasts.

It will take a lot of sword strikes to defeat him. When you do, he will disappear for good. Now, for the next one!

Golden Lynel



 * Location: Tarm Ruins (chapter 6)
 * Season: winter

Can be found in Tarm Ruins during Winter. As with the previous ones, using the boomerang will make this a relatively easy battle.

Golden Darknut

 * Location: Western Coast (chapter 7)
 * Season: spring

This monster can be found east of the Heroes Cave. You must have the pirate ship "parked" in between the two bridge parts to be able to get to the stump.

After you've killed all four of the Golden Beasts, head back to to collect your reward, the Red Ring, a ring that doubles sword damage without decreasing Link's defense.