The Scourge Invasion of Azeroth has begun once again in World of Warcraft: Wrath of the Lich King Classic with the start of the Zombie Plague event. This event marks the first major event during the World of Warcraft pre-patch event for Wrath of the Lich King Classic.

The Scourge Infestation is an infamous event from the Wrath of the Lich King pre-patch event, which allows players to become Plague Zombies in service to the Lich King. Crates of plagued grain begin to show up in some cities, which infect players who interact with them. If the disease is not cleansed by a character or one of the Argent Healer NPCs, they will be turned into a Plague Zombie.

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While a Plague Zombie, a player gains new abilities and becomes able to attack any player or NPC–and continue to spread the plague. As time progresses, more crates will spawn and the plague’s incubation time will shorten. This will quickly cause Orgrimmar, Stormwind, and other major World of Warcraft hubs to become zombie-filled wastelands.

Starting September 13, Wrath of the Lich King Classic will begin the Scourge Invasion proper. In addition to the ongoing Zombie Plague, Scourge Invasion points will appear in select regions of the world. Players can also investigate Scourge activity within the major cities and can find special bosses in certain World of Warcraft dungeons, all of whom drop some exclusive rewards. These events will last for two weeks until Wrath of the Lich King Classic’s launch on September 26.

The Wrath of the Lich King pre-patch events are some of the most notorious and fondly-remembered in-game events in World of Warcraft’s history. The second pre-patch in history, the Scourge Invasion refined the model from Burning Crusade and set a high standard for future pre-expansion events. Many players are excited to relive the iconic moment in World of Warcraft’s history–especially the worldwide PvP event that is the Zombie Plague.

Nevertheless, there are some fans who are less enthusiastic about the Scourge Invasion event. As before, there is no way to opt-out of the Zombie Plague event, meaning players hoping to go about their business in World of Warcraft will be faced with hordes of zombies trying to kill them and the NPCs they need to interact with. Players uninterested in participating in it should stay away from major cities if they want to avoid being inconvenienced by swarms of zombies over the next few weeks until Wrath of the Lich King Classic’s launch.

World of Warcraft is available on PC. Wrath of the Lich King Classic launches September 26.

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