Great Bay Coast
34. What you need: Goron Mask
In the Pirate Lagoon Fortress, there's a heart piece in a cage. Step on the switch with Goron Link and roll down into the cage while the door is open.
35. What you need: Picture of Gerudo Pirate, 1 Empty Bottle, Zora Mask
Give a picture of a Gerudo Pirate to the guy in the house at Great Bay Coast. In exchange, he'll let you take the seahorse. Take the seahorse to Pinnacle Rock and let him guide you to the crater. Defeat all of the sea snakes to reunite the seahorse with his friend to get a piece of heart.
36. What you need: Captain's Mask (optional), Hero Bow
Go to the House of Skulltula and find the room with the colored masks. Talk to the Stallkids with the Captain's Mask and they'll tell you what order to shoot the colored masks in. After you shoot them, the fireplace will open with a piece of heart inside.
37. What you need: Goron Mask, Mountain Title Deed
At Zora Hall, go to LuLu's room and put on the Goron Mask. Talk to the Deku Scrub and give him the Mountain Title Deed to get the piece of heart just above the flower.
38. What you need: Zora Mask
On the west side of Great Bay Coast, go to the waterfall. Underneath it is a LikeLike. Dive down and kill it to get a piece of heart.
39. What you need: Zora Mask
At Zora Hall, go to the drummers room and hookshot to the top ledge. Read the diary and learn to parts of a song. Now go to the next room on the left and play the song with Japas. Now memorize that whole song and play it for the band leader with your Ocarina and he'll give you a piece of heart.
40. What you need: 4 Bottles of Fish
At the Marine Lab, Feed the large fishes in the tank near the door 4 bottled fishes (possibly 5). One will grow really big and eat the other one. That fish will spit out a piece of heart.
41. What you need: Scarecrow Song, Hookshot, 1 Magic Bean, 1 Bottle of water
Close to where the Pirate's Lagoon is, there's a bunch of platforms. Hookshot onto one of them. Make your way to the one with a patch of soft soil and plant your magic bean. Ride the plant to the next ledge. Play the Scarecrow Song and hookshot to him to get another piece of heart.
42. What you need: Hookshot
After defeating the Great Bay Temple, find the boat close to where the platforms are mentioned above. Ride it over to a small group of islands and hookshot onto the tree where the fisherman is standing. Play his game to win a piece of heart.
43. What you need: Zora Mask
Make your way to the Beaver races at the top of the waterfall in the western area of Great Bay Coast. Beat the two beavers once to get a bottle. Beat them a second time to get a piece of heart.