Item Upgrade in World of Warcraft
Item upgrade is a system that allows players to raise the level of their weapons, armor and trinkets beyond what they can obtain from specific Mists of Pandaria and Warlords of Draenor sources. It requires crests and currencies and can be completed at any item upgrader (look at this website) NPC.
Items that have high requirements (eth titans, for example) typically increase in value after upgrading. Items with lower requirements are given a slightly less value as they are able to be used in a perfect manner regardless of whether they upgrade.
Reroll tokens
Reroll tokens are special items that can be used to upgrade an item upgrader kit. Monsters and event rewards can give them. They are available in three types: rare, enhanced or legendary. If a player owns a reroll token they can right click a Satanic or Angelic item and select the option to reroll the quality of the item. This process will consume the token used to reroll.
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