Customize

General
To customize something in Guild Wars means to attune an item to a specific character. This makes the item only usable by that specific character.

Effect of Customization
There are two kinds of customizations in the game:
 * Weapon Customization: When a weapon is customized for a character, it deals 20% more damage. The draw back is that no other character (even for the same account, or a new character with the same name) will be able to use it. This makes its resell value next to nothing. If you get a weapon that you plan to use for the long run, then it's a good idea to customize it, especially for warriors and rangers who rely on dealing damage with their weapons. If you plan to sell the weapon, then do not customize it.
 * Armor Customization: Any armor crafted in the game will be customized specifically for the character that purchased it. This is by design and there is no way to avoid it.

Note: A customized item will have the phrase "Customized for ..." in its description when the mouse is hovered over it.

How to Customize

 * Weapons: This is done by going to a Weapon Crafter in a city or outpost. In the merchant window that appears there will be a tab called Customize. Click on it and choose the weapon in your inventory that you wish to customize then click on the Customize button at the bottom of the screen. Weapon Customization always costs 10 gold.
 * Armor: Armor will always be customized.

Other Players' Customized Items
As mentioned above, a player cannot use an item customized for a character other than the one he/she is playing with. Customized items can be sold to merchants (for prices far below what it cost to craft them). They can also be salvaged for materials, weapon upgrades, or runes.

Note that if you have an item customized for character A, put the item in storage, delete character A and make new character with the exact same name, the new character still cannot use the customized item.

Warning: Beware of scammers trying to sell customized items.