Transmogrification

Transmogrification (sometimes abbreviated Transmog, or just Mog) is a gameplay feature of Diablo III and Diablo IV.

Diablo III
Transmogrification was introduced in the Reaper of Souls expansion pack. Provided by the Mystic artisan, it is designed to increase a hero's customization. Transmogrification gives players the ability to modify the appearance of their armor and weapons without compromising any of their power or potency.

Transmogrified items can be dyed in the same manner regular items are (and retain the dye already applied). The process only costs gold: standard price is 500, but transmogrifying an item to have a legendary item appearance costs 50,000. In addition, for weaponry, the price increases if the player wishes the appearance of a high-leveled weapon, up to 50,000 in gold. Unlike Enchanting, repeated transmogrification of the same item will not raise the price. Reverting the item back to its original appearance is always free.

Limitations
Transmogrification shares a restriction with dying items in that anything that is not seen on the character, such as jewelry, belts, and bracers, cannot have transmogrification done on, no matter the quality. In addition, if there is a Legendary or Set item appearance one wants to have, he/she must find/craft that item in-game and identify it for it to be unlocked.

The amount of types each item can use for transmogrification is limited.


 * Class-specific items can be transmogrified into both regular equivalents (example: Crusader shields and regular shields) and class versions, but regular items can only be transmogrified into class-specific versions by the class that can use them (for other classes, it will appear as having no transmogrification).
 * Weapons can be transmogrified into different types (swords to maces and axes, for example). Not all types are interchangeable.


 * Class-specific items that do not have a direct equivalent (Wands, Hand Crossbows, Fist Weapons) can only be transmogrified within their own type.
 * Appearances of items that are restricted to a specific class (such as level 70 class sets) can only be used for transmogrification by the class that can wear them: other classes won't be able to see the altered appearance if they equip this item. Therefore, it is impossible to make one's items appear like those restricted to another class.


 * A general rule for weapons: transmogrification requires the same animation set, to avoid visual bugs. Some parallels, however, can be quite unexpected, such as Daggers and Spears.

Cross-class sets
The following item sets can be worn by any class; making them available for transmogrification by any class.


 * Blackthorne's Battlegear – Any
 * Heritage of Arreat - Barbarian
 * Immortal King's Call – Barbarian
 * Inna's Mantra – Monk
 * Might of the Earth – Barbarian
 * Monkey King's Garb – Monk
 * Natalya's Vengeance – Demon Hunter
 * Raiment of the Jade Harvester – Witch Doctor
 * The Shadow's Mantle – Demon Hunter
 * Tal Rasha's Elements – Wizard
 * Thorns of the Invoker – Crusader
 * Vyr's Amazing Arcana – Wizard
 * Zunimassa's Haunt – Witch Doctor

Whimsy Legendaries
The Horadric Hamburger and Spectrum are secret legendaries, found only in Whimsyshire and Whimsydale. They were designed specifically for their unique appearance. Originally intended as a joke (as the weapons are impractical for combat), they now hold value as transmog only items.

Transmogrification Items
In patch 2.4 Lachdanan's Stormshield was added to the game. Its only purpose was transmogrification.

In patch 2.4.1 several more 'transmog only' items were added:

Armor:
 * Helm of Cranial Crustacean
 * Star Helm
 * Star Pauldrons

Swords:
 * Amberwing
 * God Butcher
 * Ghoul King's Blade
 * Quinquennial Sword
 * Second Quinquennial Sword

Flails:
 * Flail of Carnage
 * Templar's Chain
 * The Que-Hegan's Will

Fist Weapons:
 * Hand of Despair
 * Panther's Claw

2-Handed Axes:
 * Kanai's Scorn
 * Sungjae's Fury

Other:
 * Aidan's Revenge (Axe)
 * Crossbow of Corvus (Crossbow)
 * King Maker (2H Mace)
 * Mace of the Crows (Mace)
 * Man Prodder (Polearm)
 * The Reaper's Kiss (Staff)
 * Steffon's Heavy Lance (Spear)

Trivia

 * Transmogrification originally appeared in World of Warcraft, with exactly the same functionality.

Transfiguración