Keys are items formerly available in the Chinese version of Plants vs. Zombies 2 and currently available in Plants vs. Zombies Online. The player needed them to open gates, therefore gain access to a certain upgrades, plants and Brain Busters levels. There were different variations of keys for each world when they existed in the Chinese version. However, in Plants vs. Zombies Online, there is only one type of key.
Keys were also originally in the international version of Plants vs. Zombies 2, but were removed in the 1.7 update, as a new method of unlocking plants and rewards replaced the original layout. Any keys the player had before the update were turned into coins. World progression now takes place through the use of World Keys obtained by defeating the Gargantuar level for the first time in any world.
In Plants vs. Zombies Online, keys are mainly obtained by beating levels for the first time in Adventure Mode. Subsequent replays of the beaten level will not give the player any more keys.
How to obtain
Keys are found as a rare drop off of all zombies killed in a time zone. The odds of a zombie dropping a key are relatively low, around one percent off of any zombie, regardless of health or speed. Keys could also be found off of the Treasure Yeti every once in a while, and a lunchbox can carry three keys of the area the Yeti was killed in.
- Killing the Treasure Yeti was one of the best ways to get keys, as every other lunchbox has three keys.
- Playing levels with a high zombie density provides more chances for keys to drop.
- Completing Piñata Parties could have resulted in a few keys being rewarded.
- Zombie strength does not effect drop chances, so it was more practical to battle large amounts of weaker zombies for key farming.
Plants vs. Zombies 2
Plants vs. Zombies Online
- Each gate involved three to five keys to be unlocked, except for the Special Delivery gate in Ancient Egypt, which involved one key.
- In the pre-1.7 versions of Plants vs. Zombies 2, Piñata Party piñatas had a chance to carry one key for any area, as long as they player had that area unlocked.
- The maximum number of keys can be stored at a time is 99; any more collected will not increase the counter past the maximum.
- The 1.8 update of the Chinese version removed the key system.
- The key from Frostbite Caves is the only key to be not made of gold, as it is made of ice.
- It is also shaped like a regular key with no symbol on the top of it.