100% Completion

100% Completion refers to having mastered all aspects of a title. The Permanently Missable Items article is useful to those undertaking this challenge. Like the Three Heart Challenge and Speed Runs, 100% Completions are an optional challenge for The Legend of Zelda series fans.

To brag of having a 100% Completed file, one must have all Heart Containers, Weapon upgrades, Items, and Collectible items such as Ship Parts. Unlike other gaming series like Metroid or some Mario games, the Legend of Zelda series thus far has no in-game rewards (such as alternative or lengthened endings for the feat) or even bragging rights rewards that acknowledge the completion. Although finding every last collectible is difficult in its own rights, doing so makes gameplay easier than Speedruns, Minimal Completions, and Three Hearts Challenges.

The Legend of Zelda
Most Difficult Aspect- Beating the game Checklist
 * 16 Heart Containers.
 * Both Bomb Capacity Upgrades.
 * Boomerang upgraded.
 * Magical Sword obtained.
 * Arrows upgraded to Silver Arrows.
 * Blue and Red Rings obtained.
 * Shield upgraded to Larger Shield.
 * All Dungeon Items Obtained.
 * Complete both Quests.

The Adventure of Link
Most Difficult Aspect- Beating the game Checklist
 * All 4 Heart Containers.
 * All 4 Magic upgrades.
 * Level 8 Life experience.
 * Level 8 Magic experience.
 * Level 8 Attack experience.
 * All 1-Up Dolls.
 * All spells.
 * Upward and downward stab attacks.

A Link to the Past
Most Difficult Aspect- Beating the game Checklist
 * All 24 Pieces of Heart found.
 * All four bottles obtained.
 * All items obtained.
 * Red Boomerang obtained.
 * Master Sword tempered to level 3.
 * Red Mail obtained.
 * Magic Meter halved.

Gameboy Advance remake (The Gameboy Advance remake included several new features, extending the checklist)
 * Four Swords completed.
 * Palace of the Four Sword completed.
 * Lumberjack sidequest completed.

Link's Awakening
Most Difficult Aspect- This is a matter of personal opinion. Checklist
 * All 12 Pieces of Heart found.
 * Trading Sequence completed (culminating with the Boomerang).
 * Sword upgraded to level 2 (Seashell Sword).
 * Magic Powder carrying capacity upgraded to 40 units.
 * Bomb carrying capacity upgraded to 60 units.
 * Arrow carrying capacity upgraded to 60 units.

Ocarina of Time
Checklist
 * All 36 Pieces of Heart found.
 * First four Happy Masks sold (with the availability of the other four masks being the reward).
 * All upgrades (Deku Nuts and Bombs up to 40, Deku Sticks up to 30, Arrows and Deku Seeds up to 50, Rupees up to 500, and the Golden Scale and Golden Gauntlets).
 * Equipment complete (including the Biggoron's Sword).
 * All Skulltulas killed, receiving the rewards (and, although optional, receiving a Huge Rupee after talking to the last cursed man as thanks).
 * All four bottles.
 * All items (including the Ice Arrows).
 * Retrieving Epona, having the cow from Lon Lon Ranch in Link's house after winning Malon's racing minigame.
 * Racing the running man from Gerudo Valley at least once (as it saves the time record inside the list of greatest deeds at Link's house).

Majora's Mask
Checklist
 * All 52 Pieces of Heart found.
 * Collecting the Fierce Deity's Mask (which provides that all other masks were found as well).
 * All six bottles.
 * Bomber's Notebook complete.
 * All Stray Fairies rescued (and the rewards received).
 * Sword tempered with Gold Dust, Mirror Shield obtained.
 * All upgrades (Bombs up to 40, Arrows up to 50, Rupees up to 500).

Oracle of Ages
Checklist

Oracle of Seasons
Checklist

The Wind Waker
Checklist
 * All 44 Pieces of Heart found.
 * All 61 Charts collected (and, in the case of the 41 Treasure Charts, all treasures must have been collected).
 * All four bottles.
 * All upgrades (Bombs and Arrows up to 99, Rupees up to 5000).
 * Hero's Charm and Magic Armor collected.
 * All 12 possible souvenirs obtained in the trading sequence available at Zunari's Shop.
 * All three types of potion prepared in Doc Bandam's shop.
 * At least 60 purchases made in Beedle's Shop Ship.
 * Nintendo Gallery complete.

The Minish Cap
Checklist
 * 100 Kinstone Fusions (and Kinstone Bag converted to Tingle Trophy)
 * 44 Pieces of Heart found
 * Full Heart Container found
 * All 4 bottles obtained (requires completion of Goron Sidequest)
 * All 8 Golden Monsters defeated
 * All 136 figurines obtained
 * Magical Boomerang obtained
 * Mirror Shield obtained (requires completion of Goron Sidequest)
 * Bomb carrying capacity upgraded
 * Remote bombs
 * Arrow carrying capacity upgraded
 * Light Arrows
 * All 8 Tiger Scrolls obtained
 * All 4 Sword Technique upgrades obtained
 * Wallet capacity upgraded to 999 rupees
 * Homes found for 2 of Din, Nayru and Farore
 * All 3 Joy Butterflies found
 * All 8 Swordsman Newsletters
 * All 6 colours of Picolyte made available

Twilight Princess
Checklist
 * All 45 Pieces of Heart.
 * All upgrades (three Bomb Bags plus the Big Bomb Bag that doubles the capacity of the bombs currently stored; arrows up to 100, Rupees up to 1000).
 * All four bottles.
 * All 24 Golden Bugs collected.
 * All 60 Poes captured (and, although optional, receiving 200 Rupess from Jovani, talking to him in the bar and then receiving 200 Rupees from his cat at least once).
 * Equipment complete (including the Magic Armor).
 * All seven Hidden Skills learned.
 * All types of fish captured.
 * Level 8-8 of Rollgoal completed.

Phantom Hourglass
Checklist
 * All 16 Heart Containers.
 * All 20 Power Gems.
 * All 20 Wisdom Gems.
 * All 20 Courage Gems.
 * All 31 Treasure Charts.
 * All upgrades (Bombchus and Bombs up to 30, arrows up to 50).
 * Great Spin Attack learned.
 * All Ship Parts collected.

Spirit Tracks
Checklist
 * The Stamp Book completed.