Windfury Weapon is an Enhancementshaman temporary weapon imbue that gives each main-hand melee attack a chance to strike two additional times, dealing damage based off attack power. Windfury Weapon is available at level 10.
Consumable imbues (ex. [Shaded Weightstone], [Shadowcore Oil]) should never be considered over Windfury Weapon. These imbues do not compare in terms of damage for enhancement, and unlike Windfury Weapon they have no synergy with the shaman's mastery, talents, or abilities.
Windfury Weapon quickly gained notoriety during the original World of Warcraft run for its ability to sometimes "one-shot" players. This was due to its strong tuning and relied on the use of slow two-handed weapons. Low-armor classes were primarily susceptible, specifically Mages and Priests as their base health pools were the lowest in comparison to other classes. Newer level 60s were also susceptible if they were under-geared.
This phenomenon occurred less often after the nerf that was made in patch 1.11.0, and all but disappeared in patch 2.0.1 when enhancement gained the ability to dual wield weapons.
Despite the nerf, geared enhancement shamans are still capable of these "one-shots" with Windfury Weapon procs in Classic.
Windfury Weapon was bugged prior to patch 1.4.0, which allowed it to incorrectly cause a 3rd extra attack, and also incorrectly reset the swing timer upon proc. This caused the next normal swing to happen instantly, which was also capable of a Windfury proc.
Originally this internal cooldown was tied to the rank used, allowing enhancement shaman to increase their proc uptime by using a lower rank on their off-hand. With patch 2.1.0 the internal cooldown became shared across all ranks.
Patches and hotfixes
Patch 9.0.2(2020-11-17): Windfury Weapon's proc damage has been increased by 240%.