Adept

From Guild Wars Wiki

Adept is a weapon upgrade that grants a 10-20% chance that spells will cast twice as fast. This bonus only applies to spells that share the same attribute as the requirement on the item this upgrade is attached to.

[edit] In-game description

Halves casting time of Attribute spells (Chance: 10-20%)

[edit] Upgrade components which provide this bonus

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