World Item

World Class Items (世界級アイテム, Sekaikyū Aitemu) or World Item (ワールドアイテム, Wārudoaitemu) are the most powerful and dangerous legendary items in YGGDRASIL, as they possess massive power that could damage the game's balance, thus, earning them the term "Balance Breakers".

Overview
In all of YGGDRASIL, there were only 200 World class items.

Each of them had their own unique ability, and some were powerful enough to destroy the game's balance. Of course, not all of the World class items had such game-breaking abilities. Even so, if a player managed to get hold a World class item, that player's reputation in Yggdrasil would jump to the highest level. Effects of a world class item can be resisted in only two ways : (1) Owning another world class item. (2) Getting special classes.

Twenty
"Twenty" is the name of 20 world class items that are unrivaled in terms of power. All of them could only be used once. If one needs to use it again, one should find the item all over again, regardless of difficulty of the process.
 * Longinus: has the power to completely remove any target from existence at the expense of the user's own existence. This removal can only be reverted by using another special world class item.


 * Ahura Mazda: has massive effects to anyone with evil karma. It can even change the world.


 * Five Elements Overcoming: has the power to request the developers to change the magic systems of YGGDRASIL.


 * Ouroboros: has the power to alter YGGDRASI's game mechanism, in more various ways than Five Elements Overcoming. It once prevented Ainz Ooal Gown guild members from entering a certain area.


 * World Savior: A club-shaped item. Very weak in its initiatory stage, but gets stronger with time. It can become so strong that it can even conquer Nazarick with all the members of Ainz Ooal Gown.


 * Caloric Stone: Exact power is unknown. Can only be gained by using massive amounts of rare metal from seven hidden mines. One belonged to Ainz Ooal Gown. Guild member Nubo proposed to make invincible golems using this item.

Other World Class Item

 * Downfall of Castle and Country: The user can mind control even those with absolute mental resistances.


 * Avarice and Generous: A gauntlet. One side looks like a devil's hand while the other side looks like an angel's. Given to Mare from the treasury.


 * Grail of Hygieia: Unknown. Given to Demiurge or Cocytus from the treasury.


 * Billion Blades: Unknown. Given to Demiurge or Cocytus from the treasury.


 * Picture of Nature and Nation: Big scroll, given to Aura from the treasury. Has the power to isolate an object to a different dimension.


 * True Nought, Ginnungagap: World class item of Albedo. It seems like it can be used to destroy large areas. Tabula gave it to Albedo without permission from the rest of the guild. Ainz noticed only just before the game was about to end so he let it slip by.


 * Atlas: Unknown. Once belonged to Ainz Ooal Gown, but a guild stole it. It does not exist in treasury anymore.

Unnamed World Class Item

 * World class item that summon devils: An item that summons an endless legion of very strong demons, making a lot of trouble in Yggdrasil. It is unknown if it is one of the "Twenty".


 * Other world class item in the throne hall: Unknown.


 * Ainz's world class item: unknown. If Ainz activates this item, he will lose some levels.


 * World class item from the 8th floor: Unknown. Once it belonged to a female NPC in the 8th floor. Now the item is given to Shalltear.

Trivia

 * Ainz Ooal Gown has 11 world class items.
 * Five Elements Overcoming means overcoming relationships among five elements in Taoism. "Gogyosoukoku" in japanese pronunciation.
 * Downfall of Castle and Country means a really beautiful woman who can make even a country to fall, like Helen in Trojan war. "Keiseikeikoku" in japanese pronunciation.
 * Picture of Nature and Nation refers to a Chinese legend of a man going into a picture and live in there.
 * According to the game lore of YGGDRASIL, the World Class Items are made from the remains of fallen leaves from the World Tree.
 * The World Class Items have the power to override 「Wish Upon a Star」’s magic.
 * Nazarick is protected by having a world items against world items.