World Key

The World Key is an item available in Plants vs. Zombies 2 that allows the player to unlock new worlds. The player can get one after beating the Gargantuar level in any world. They were added in the 1.7 update, replacing stars as the means of unlocking other worlds.

In the Chinese version, a World Key can be obtained by either beating the last Day in the first three worlds, or by beating the level before the first boss level in the rest (Day 16 and Day 30 in Kung-Fu World, Day 29 in Far Future, Night 30 in Dark Ages, and Day 30 in Big Wave Beach and Day 25 in Frostbite Caves, Day 24 in Castle in the Sky and Day 25 in Lost City).

Additionally, a free World Key is given to all players since the 3.5.1 update as a reward by beating Ancient Egypt - Day 2. This key is won for all players by YouTuber ZackScottGames when he completed a Piñata Party challenge set by the PopCap team.

Usage
It can be used to unlock any world, according to the description. Therefore, the player can go to any world in any order they want to. The player should be careful to what world he or she will unlock, so an ideal order of worlds being unlocked is Pirate Seas, Far Future, Lost City, Frostbite Caves, Wild West, Neon Mixtape Tour, Jurassic Marsh, Dark Ages, Modern Day and Big Wave Beach. This order may help tame the stressing difficulty of the four to five Jalapeno difficulty worlds. If stuck the player may use their extra key to overcome the stress.

Trivia

 * The player can only get more World Keys if the player decides to purchase a world instead of using a World Key, getting a free World Key, or unlocking Pirate Seas after beating Ancient Egypt - Day 12 for a limited time during April 2014 since the player didn't need to use the World Key.
 * Each Gargantuar statue that is present in each area holds a World Key.
 * From Lost City and onward, all the Gargantuar level statues are different, now being a sculpture of the Gargantuar's fist holding the World Key.
 * The advertisement for World Keys claim that the player will find Gargantuars in Day 8 of each world. However, this is not true in Dark Ages and later worlds.
 * The Chinese version of Plants vs. Zombies 2 contains both stars and World Keys, the former being used to obtain plants.
 * In earlier versions, there was a glitch in which the player could randomly receive a large number of World Keys. This was fixed in a later update.

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