Greedy Gibdos
Beneath the well lies a sizeable ruin that’s filled with greedy Gibdos. Put on the Gibdo Mask that you recently found, and you’ll be able to speak to the Gibdos. Have a chat with the Gibdo to the north. It hints that it wants some medicine that bestows health. Give it the Red Potion that you bought from the Trading Post, and the Gibdo vanishes, letting you open the door it was guarding and explore more of the ruin.
Two spike traps lie beyond the north door. Before bolting past the traps, enter the west alcove, and scoop the fish in the water into an Empty Bottle.
Now for the spike traps, which spin before moving up or down. Watch for them to spin, and make your way past when it’s safe.
Once you’re past the spike traps, a Gibdo appears right in front of you. Ignore this one, turn left, and then speak to the Gibdo to the west. Give the Gibdo the fish that you’ve just caught, but don’t go through the door it had been guarding. The door merely leads to a hot spring that you don’t need to visit yet.
Instead, backtrack to the ruin’s entrance. This time, speak to the Gibdo that guards the east door. Give this Gibdo the Magic Bean that you’re carrying, and it lets you pass. Go through the door to explore the ruin’s east passages.
After passing through the door, duck into the north alcove, and melt down the Freezard with a Fire Arrow. Cut down the circling Keese and the Deku Babas in the corner, as well, making sure to collect the Deku Sticks that the Deku Babas drop. Lastly, fill an Empty Bottle with Spring Water from the nearby pool.
Exit the alcove, and go east to find two more Gibdos. One stands near the north door, and the other stands near the east door. Beware the Wallmaster that drops from the ceiling as you head for the east Gibdo. Give the east Gibdo a Deku Nut to gain access to the east door, but don’t go through it just yet.
Hot Spring Sprint
Backtrack to the ruin’s entry and return to the hot spring up north, beyond the spike traps. Stand near the fire traps, and throw Zora Link’s fins at the Dexihand that guards the steaming pool. Dart past the fire traps afterward, and then fill a bottle with Hot Spring Water. Put on the Bunny Hood, and sprint back to the entrance. Make your way back to the east door that the Deku Nut Gibdo had been guarding.
Go through the east door that the Deku Nut Gibdo was guarding, and then sprint straight toward the Gibdo that’s directly ahead of you (to the east). Put on the Gibdo Mask as you draw near, and then give the Gibdo the Hot Spring Water that you’re carrying. You’ve got to be quick, or the Hot Spring Water cools and turns into normal Spring Water.
Mood Moosic
After the Gibdo leaves, go through the east door to find a cow grazing away. This gal’s a long way from Romani Ranch, so play her Epona’s Song to bring back memories of the pasture. Epona can’t join you here, but the cow returns your kind gesture by filling one of your bottles with milk.
Leave the cow to her grazing, and backtrack down the previous passage. As you go, enter the south alcove to discover a bunch of bugs. Catch two bugs in two bottles.
Leave the bug alcove, and go east and then north to find another nearby Gibdo that guards the north door. This one wants a bomb. Hand one over, and then enter the north door.
Big Poe Battle
The room beyond the north door features four blade traps. Avoid them, and move to the room’s center to summon a monstrous Big Poe. Lock on, block the Big Poe’s spinning charge, and then shoot it with an arrow. Repeat this until you defeat the Big Poe.
After defeating the Big Poe, approach its ethereal remains and scoop them into a bottle. You’ll soon be needing this Big Poe’s soul.
You should now be carrying some Spring Water, some milk, two bugs, and a Big Poe’s soul in your bottles. Backtrack to the entry, and go through the north door. Move past the spike traps, and then speak to the Gibdo that guards the next door to the north. Give this Gibdo regular Spring Water to make it depart, then go through the north door that it was guarding.
More spike traps lie beyond the north door. Ignore them, and use a Fire Arrow to melt the webs that block the nearby alcoves. Enter the west alcove, and fill your bottle with another bug. You should now be carrying three bugs, some Milk, and a Big Poe’s soul.
Slip past the spike traps, watching out for a Wallmaster that drops from the ceiling beyond them. Slay it if you can, then speak to the north Gibdo. Give the Gibdo a bug to make it depart, then go through the north door.
Fairy’s Fountain
A Fairy’s Fountain lies beyond the north door. There’s no Great Fairy here, but you can heal your wounds and catch a few Fairies, if you like.
Leave the Fairy’s Fountain, and slay the Wallmaster again. Then, speak to the other nearby Gibdo guarding the east door. Give this Gibdo a bug also to make him bug off, then go through the east door.
Fire Keese’s Secret
Slay all of the Fire Keese in the small room beyond the east door, then use the Lens of Truth to spy an invisible chest. Open it to claim a Purple Rupee.
Fire Keese
Damage: 1/2 Heart
This brand of Keese flies about aflame, aiming to swoop down and scorch an unsuspecting Link. Like Ice Keese, Fire Keese lose their flame after they hit Link, reverting to normal Keese. However, Fire Keese can fly through open flame sources, such as lit torches, to reclaim their flames and burn Link once more. Slay these troublesome foes with Link’s sword as they swoop close, or pick them off with arrows or the Hookshot from afar.
Backtrack out of the Fire Keese room, and slip past the spike traps. Go through the south door, get past the other set of spike traps, and then duck into the west alcove and scoop another fish into a bottle. You should now be carrying a fish, some milk, a bug, and a Big Poe’s soul in your bottles (and perhaps a Fairy or two, as well).
Return to the entry, and go through the east door. Beware the Wallmaster in the passage beyond, and speak to the Gibdo that guards the north door. Give this Gibdo the fish you’ve just caught, then go through the door he was guarding.
Skulltulas’ Stash
Two more Gibdos stand in the passage beyond the north door. Speak to the west Gibdo and give it your last bug. Go through the west door afterward to enter a small room that’s home to some invisible Skulltulas.
Use the Lens of Truth to help you slay the invisible Skulltulas (there are three of them), then use a Fire Arrow to light one of the room’s torches. Whip out a Deku Stick and use it to light the rest, and then a chest appears. Open the chest to pocket another Purple Rupee.
Passage of Peril
Leave the Skulltulas’ room, and speak to the other Gibdo up north. Give him the Big Poe’s soul to make him leave, then go through the north door.
The passage beyond the north door features more spike traps and two Wallmasters this time. Slay the first Wallmaster, then move past the spike traps and slay the other. Give milk to the Gibdo beyond the spike traps, and then enter the door he was guarding to visit the final chamber.
Mirror, Mirror
Sunlight floods the final chamber, which is free of threats. Use a Fire Arrow to light one of the four torches here, then use a Deku Stick to light the rest.
With all four torches lit, a big treasure chest appears. Open it to claim a valuable new item: the Mirror Shield.
Mirror Shield
You got a Mirror Shield! Press 
to assume a defensive position. If you press 
while 
-Targeting, you can move while defending yourself. This special shield can also reflect certain kinds of light.
Step into the sunlight, and hold 
to pull out your Mirror Shield. Direct a beam of light at the sun emblem on the wall to make a ladder appear. Neat!
The ladder leads up to a large block with a picture of a sun etched on it. Use the Mirror Shield again to shine light at this sun block, and it vanishes, revealing a passage. Climb the ladder and go down the passage to sneak into Ikana Castle.
Just Visiting
You’ll be storming Ikana Castle momentarily, but first, you need to buy a Powder Keg. There’s an easy way back into the castle, so don’t worry about returning here. Soar to Clock Town and visit the Bomb Shop, then put on the Goron Mask and buy a Powder Keg from the shop’s Goron for 50 Rupees.
Another Entrance
You don’t need to delve beneath the well again—there’s an easier way into Ikana Castle. Soar back to Ikana Canyon, and go east when you arrive. A nearby sign indicates that the large red gate to the east is Ikana Castle’s front gate.
The castle’s big front gate is shut tightly, but there’s a Link-sized hole just to the left of it. Go through the hole to reenter the Ancient Castle of Ikana, not far from the spot where the well’s secret passage delivered you.
