Once you get access to Termina Field, it's possible to do some sequence breaking. Walk up to the northern passage blocked by ice, Z-target the icicle from a distance, and jump to the right. If done correctly, Link will walk on the rocky outcropping adjacent to the ice. This gives you access to the Mountain Village, Goron Mask, and the Lens of Truth without having the Hero's Bow. Once you have the Goron Mask, head for the Great Bay. There's a fence blocking the path that normally requires Epona to get over, but you can use boost damage instead. Lure a ChuChu from the nearby patch of grass in Termina Field to the fence. Switch to Goron form and use his ground pound jump. If timed correctly, the ChuChu will hit you at the apex of the jump, triggering Link's falling/damage animation and giving you enough height to clear the fence. You'll get the Zora Mask shortly afterward. If you're stocked up on Deku Nuts, you can also go to the Pirates' Fortress and obtain the Hookshot; use the nuts to stun the guards, and use Zora Link's boomerang fins to trigger the beehive and clear the treasure room. If you have some spare Deku Sticks and Bombs afterward, you'll have everything needed to complete the Oceanside Spider House, which nets you the Giant Wallet much earlier than normal. Thus you have access to all three major transformations in the game and a few great items before even setting foot in a temple.
Bomb Bag Upgrades
You can upgrade the Bomb Bag's capacity by performing a couple of tasks.
Upgrade
How to unlock
Big Bomb Bag (30 Bombs)
As a Hylian, stop Sakon from mugging the Bomb Shop Lady on the First Night. It'll be for sale for 90 Rupees at the Bomb Shop.
Big Bomb Bag (30 Bombs) (Alternative)
Alternatively, if Sakon succeeds in stealing the Big Bomb Bag, it goes on sale at the Curiosity Shop for 100 Rupees on Night 3.
Biggest Bomb Bag (40 Bombs)
As a Goron, talk to the Business Scrub in Goron Village. Trade the Big Bomb Bag and 200 Rupees for the upgrade.
Easy Clock Town Rupees
After you've regained Link's Hylian form, go to the top of the East Clock Town stairs and do a rolling jump over gap between buildings at the Eastern Gate. Continue jumping close to the wall, using the decorative targets above the Honey & Darling's Shop as makeshift platforms. Continue walking behind the Town Shooting Gallery sign until you reach a trunk containing a Silver Rupee. This treasure can be claimed once per time loop. Also, the targets above the Honey & Darling's Shop will produce several Green Rupees if you shoot them with your items or Deku Link's bubbles. This second trick resets every time the East Clock Town screen loads.
Fixing Broken Signs
After cutting a wooden sign to pieces, play the Song of Healing. The sign will magically repair itself.
Great Fairy Rewards
By collecting all of the Stray Fairies and returning them to their respective Fountains, the Great Fairies will reward you with various upgrades.
Reward
How to unlock
Charged Spin Attack
Collect all the Stray Fairies in the Snowhead Temple and return them to their Fountain.
Defense Boost (Damaged Reduced By Half)
Collect all the Stray Fairies in the Great Bay Temple and return them to their Fountain.
Double-Sized Magic Meter
Collect all the Stray Fairies in the Woodfall Temple and return them to their Fountain.
Great Fairy Sword
Collect all the Stray Fairies in the Stone Tower Temple and return them to their Fountain.
Launching Gossip Stones
Place a bomb or use the Blast Mask near a Gossip Stone. The explosion will turn the Gossip Stone into a makeshift rocket, which will launch after a brief countdown.
Mental Training Made Easy
Visit the Post Office in West Clock Town while The Postman is inside. You'll find him doing his Mental Training, and he'll challenge you to mini-game in which you have to press the A button after exactly ten seconds. Normally, the clock overhead disappears after three seconds, forcing you to guess the correct time. If you equip the Bunny Hood before speaking to The Postman, however, the clock will stay onscreen the entire time. That makes beating the Mental Training far easier.
Nintendo Items In The Bomb Shop
Take a closer look at the decorations in the Bomb Shop. The big machine behind the counter is partly made from a GameCube, including the four controller ports, memory card slots, and a GBA adapter. To the right, there's a Ultra Hand, a toy designed by Gunpei Yokoi in 1966.
Quick Rupees
In south Termina Field, near the Milk Road entrance, you'll encounter a large bird that hits you and steals rupees. However, if you hit it several times and kill it, the bird leaves behind a golden rupee. This is extremely useful near the beginning of the game, and you can repeat the process as often as you like by entering and exiting the area.
Quiver Upgrades
Link's quiver can hold up to 20 more arrows by getting the following quivers. Note that the order you play the minigames in does not actually matter as to which quiver you receive.
Upgrade
How to unlock
Large Quiver (holds 40 arrows)
Get a score of 40 or more at the Town Shooting Gallery.
Largest Quiver (holds 50 arrows)
Get a perfect score at the Swamp Shooting Gallery.
R.O.B. In The Curiosity Shop
R.O.B., one of Nintendo's iconic characters, is hidden in the Curiosity Shop. However, you can't see him if you enter from the front entrance. You have to access Kafei's Hideout, which is only accessible on Day 2 if you put Anju's letter in the mailbox, then go inside while Kafei is retrieving the letter. Inside, Kafei will show you a peep hole that looks into the back of the Curiosity Shop. If you pan the camera to the right, you'll see R.O.B. sitting on a shelf.
The Inverted Song Of Time
Unlike other songs, you don't need to learn the Inverted Song of Time from anyone. With the Ocarina of Time equipped, press the buttons: RLYRLY. It'll show up in your song list. Playing it slows down the passage of time, thus letting you get more done during each time loop.
The Song of Double Time
Unlike most of the other songs, the Song of Double Time isn't directly taught to you; the Scarecrows in Clock Town will mention it without actually showing you the notes. After speaking with a Scarecrow, equip the Ocarina of Time and press YYLLRR. It's appear in your song list afterward. It allows you to skip to any hour of the given day.
Wallet Upgrades
You can upgrade the wallet's storage capacity by performing a couple of tasks.
Upgrade
How to unlock
Adult Wallet (200 Rupees)
Deposit 200 Rupees in the Clock Town Bank.
Giant Wallet (500 Rupees)
Collect all the Gold Skulltula Tokens in the Oceanside Spider House.
