The Rusty Key is a boost item which is the missing key for the Mausoleum. It is not available in the Market and can only be pieced together by winning Rusty Fragments from Invasions.
Text: A spooky key!
After you have combined 3 Rusty Fragments you can use the Rusty Key to unlock the Mausoleum which will allow you to store Zombies.
This boost was added in Version 0.78
Trivia[]
- In Zombie Farm 2 the Mausoleum is already unlocked upon purchase making this boost item obsolete.