Gratitude Crystals play an important role in The Legend of Zelda: Skyward Sword HD. They're first introduced during the Lost Child side quest and can be used to acquire wallet upgrades and other useful items from the friendly monster Batreaux. He's hoping to get hold of enough of them to eventually transform into a human and so asks Link to help him find as many crystals as possible to facilitate the change.

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In total, there are 80 Gratitude Crystals for players to find and collect, with the vast majority of these being given to Link as rewards for completing some of the game's many side quests. There are also an additional 15 Gratitude Crystals scattered around Skyloft and the many floating islands that surround it, although not all of these can be collected right away.

The more Gratitude Crystals players collect, the more they'll be rewarded by Batreaux. In total, there are eight different rewards on offer, with four of them being upgrades to Link's wallet. Those looking to buy some of the game's more expensive items will therefore need to dedicate some time to finding Gratitude Crystals, though the game can still be completed without doing so.

• 5 Gratitude Crystals - Medium Wallet (500 Capacity)
• 10 Gratitude Crystals - Piece of Heart
• 30 Gratitude Crystals - Big Wallet (1,000 Capacity)
• 30 Gratitude Crystals - Cursed Medal
• 40 Gratitude Crystals - Gold Rupee (300 Rupees)
• 50 Gratitude Crystals - Giant Wallet  (5,000 Capacity)
• 70 Gratitude Crystals - 2 Gold Rupees (600 Rupees)
• 80 Gratitude Crystals - Tycoon Wallet  (9,000 Capacity)

There are plenty of side quests for Link to complete in Skyward Sword HD, although not all of them will reward the young adventurer with Gratitude Crystals. In fact, only 12 of the game's side quests will contribute towards Link's total stash of Gratitude Crystals, with one of them providing Link with ten crystals and the rest of them offering up five a piece for a grand total of 65.

The Lost Child side quest can be initiated once Link has acquired the Ruby Tablet and is handed out by a woman named Wryna. Players will need to follow a series of clues to track down her missing daughter Kukiel and then return her to her worried mother to receive their reward.

Once players have found Kukiel they'll be able to initiate the Missing Sister side quest by speaking with Parrow in the Plaza area of Skyloft. The quest involves finding Parrow's sister Orielle and then delivering some medicine to her injured Loftwing. Both siblings will reward Link with five Gratitude Crystals each, making this the most profitable side quest in the game.

To begin the Item Check Crush side quest, players will need to have found Kukiel and spoken with the woman at the Item Check at Skyloft's bazaar on seven or eight different days. She'll eventually develop a deep infatuation with the hero, and he'll need to make a difficult decision about how to handle the situation.

Players won't be able to complete the Cleaning Pipit's House side quest until after they've acquired the Gust Bellows from the Lanayru Mining Facility. As soon as they have the item, they'll be able to earn five Gratitude Crystals and a red Rupee by blowing away all of the dust in Pipit's dirty house.

Although players can begin the Fledge's Workout side quest after first visiting the Lanayru Mining Facility, they won't be able to complete it until defeating Tentalus on the Sandship. The quest involves giving Fledge a few Stamina Potions to improve his endurance during workouts.

After players have repaired Scrapper and reached the Isle of Songs, they'll be able to initiate the Fixing Fun Fun Island side quest by speaking to Dodoh on the titular island. He'll ask Link to help him find his missing party wheel, which is down near the entrance to Lanayru Desert.

Players can initiate the Haunted Rest Room side quest after defeating The Imprisoned for the first time at the Sealed Grounds. It requires Link to follow up on some spooky goings-on in one of the bathrooms at the Knight Academy. Much like the Item Check Crush quest, players are given some choice when it comes to how events unfold.

Once players have acquired the Clawshots in the Lanayru Desert Silent Realm, they'll be able to take on the Missing Baby Rattle side quest for Bertie. They'll need to use both the Clawshots and the Gust Bellows to procure the missing baby rattle from a bird's nest that's on top of a windmill in Skyloft.

The Pumpkin Harvest side quest is handed out by Kina outside the Lumpy Pumpkin, although players will need to wait until after they've defeated The Imprisoned for the second time before they can get started. Link will need to convince Guld to help with the harvest, which results in Kina handing over five Gratitude Crystals.

After defeating The Imprisoned for a second time, players may notice that the fortune teller in the Bazaar is no longer at his station. If players visit Sparrot's house, he'll mention that he broke his crystal ball and ask Link to get him a new one. Players can find a suitable ball not too far from the Earth Temple, but they'll need Scrapper's help to recover it.

Once players have defeated Bilocyte, they'll be able to visit a new island known as Bug Rock. If they speak to Beedle at night after visiting it, he'll mention that his prized Horned Colossus Beetle has gone missing and ask for Link's help tracking it down. If players then return to Big Rock, they'll be able to win the missing beetle by completing Strich's game.

To begin the Owlan's Mystery Plant side quest, players will first need to have completed Faron's Song of the Hero quest. Visiting Instructor Owlan after this point will lead to him asking Link to find him an interesting plant down on the surface. Rather than a plant, however, Link ends up sending him a Kikwi, but Owlan is still incredibly grateful nonetheless.

If players explore Skyloft and its surrounding islands at night, they'll be able to find and collect an additional 15 loose Gratitude Crystals. Most of these are incredibly easy to find and can be collected in any order, but one or two of them are hidden in hard-to-reach places. Collecting others will require players to use specific items, meaning that not all of the loose Gratitude Crystals are accessible right away.

Players can find a Gratitude Crystal on the desk in Link's room at the Knight Academy.

There's another Gratitude Crystal on the second floor of the Knight Academy next to the plant by the exit.

The third Gratitude Crystal is on a ledge to the south of the Knight Academy. Players can either jump down there or climb the nearby vines.

Players will find the fourth Gratitude Crystal on the rear side of the Light Tower in Skyloft's Plaza area.

If players head over towards the pumpkin patch, they'll find a Gratitude Crystal hidden behind a tree.

To find the sixth Gratitude Crystal, players will need to pass through the Waterfall Cave. The crystal is between three heart flowers right by the exit.

Immediately after collecting the sixth Gratitude Crystal, players can follow the path around to find another one in the alcove where Link's Loftwing was locked up near the beginning of the game.

There's another Gratitude Crystal in the area just north of Skyloft's bazaar.

If players head inside Orielle and Parrow's house, they'll find a loose Gratitude Crystal in the corner of the room.

To find the tenth Gratitude Crystal, players will need to fly their Loftwing over to Pumpkin Landing and then sleep in one of the beds at the Lumpy Pumpkin. The crystal will then appear on one of the counters upstairs.

The eleventh Gratitude Crystal is also on Pumpkin Landing, but players will need to follow the ramp down to the storage shed in order to find it.

Once players have obtained the beetle from Skyview Temple, they'll be able to use it to collect a Gratitude Crystal from on top of one of the rafters in the Knight Academy Sparring Hall.

If players visit Beedle's Air Shop and then sleep until nighttime, they'll be able to find a Gratitude Crystal on top of one of the propellers. They won't be able to collect it without the beetle though.

After players have obtained the Clawshots, they'll be able to gain access to Zelda's room by climbing on top of the Knight Academy, grappling onto the chimney, and then jumping down it. Once inside, they'll find a Gratitude Crystal right next to the bed.

The final Gratitude Crystal will require the use of either the Clawshots or the tough beetle. It's in the water on top of the giant island with the waterfall that floats above Skyloft.

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