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
World Class items were highly relevant to the YGGDRASIL game world. According to the lore of YGGDRASIL, the YGGDRASIL World Tree was once covered with countless number of leaves.

But one day, a gigantic monster appeared and devoured these leaves. As such, the leaves were destroyed one by one, until only nine were left. These nine leaves became the world’s predecessors, called Asgard, Alfheim, Vanaheim, Nidavellir, Midgard, Jotunheim, Niflheim, Svartalfheim, and Muspelheim. However, the monster which devoured the leaves of the World Tree relentlessly pursued these remaining nine leaves.

As such, this became the background story of the game: Players would step out into the unknown and face dangers in order to protect their own world.

Each of the World Class Items are equivalent to those leaves—that is to say, each World Class item equals one world. Therefore, it was set up so that each World Class item possessed an enormous amount of power. In fact, many World Class items had extremely abnormal amounts of power that could possibly destroy a world.

The final boss of the official campaign, ‘Devourer of Nine Worlds’, is a beast that gained tremendous power from consuming the leaves and became the designated ‘World Enemy.’ The class ‘World Champion’ will only be granted to the winners of the PVP tournament, as the ones chosen by the nine worlds.

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 destabilize 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 Items

 * Downfall of Castle and Country: In Satoru Suzuki's world, it was something called a Cheongsam. It looks like a one-piece dress for women with a deep slit down the side and a round collar. The color is silvery white, with the image of a golden five-clawed dragon soaring to the skies stitched in gold thread. The user can activate it to 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.

Unknown 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.
 * In the Light novel, "Downfall of Castle and Country" is know as "Bewitching Calamity, Kei Seke Koku" instead.
 * 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.
 * 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.