Triforce Chart 4 (GameCube version -- location depends on phase of the moon) / Triforce Shard 4 (B-7)

This Triforce Shard (GameCube version: Triforce Chart 4) is hidden inside a Ghost Ship. Before you can enter this ship, you'll have to take a little detour to A-6: Diamond Steppe Isle. Sail up close to the island and use your Hookshot?on the bottom palm tree to get on top of the cliff. Drop into the hole.

This hidden cave houses some old shipwrecks -- and 15 warp cauldrons. If you don't know which ones to use, you'll be wasting a lot of time here. Basically, it's all trial and error, but here's a little map for you to help you through:

Jump into the cauldron and warp to the next area (red circle, marked 1). Go around the corner and defeat a Floor Master. Take a stick and use it to light the lid of the cauldron marked "A". Jump inside and warp to the first treasure chest. Open it to get a Joy Pendant. Hop back into the pot and burn this cauldron's lid next (below, right).

In the next area, walk forward and burn the right cauldron's lid (image below, left). Watch out for the Floor Masters. Hop into the pot. Your final cauldron to liberate (and use) is the one diagonally across from the one you came through (below, right).

Open up the treasure chest to get the Ghost Ship Chart. This handy little map lets you know where you can find (and enter) the mysterious ghost ship.

Consult the Ghost Ship Chart. The current phase of the moon will blink blue -- and next to it you can see the area of the map that's currently haunted by the ship. The shapes of the islands are easily recognizable.

Warp and sail to the area in question and scan the horizon for the ship. Approach it -- and if you have the Ghost Ship Map -- you will automatically enter it. Inside, you will have to battle a variety of enemies. Note that there's a small beam of moonlight falling in through the deck. You can use it to make the Poes solid and defeat them more quickly. Defeat all the undead and you can open the treasure chest containing Triforce Shard 4.

Video Walkthrough: Ghost Chat and Triforce Shard 4