Mario's Toadstools (blue) is part of a series of caches by Supendous-man. You can also visit Mario's Toadstools (red), a traditional cache. Mario's Toadstools (green), a multi-cache, used to be part of the series, too, but has been archived.
Originally, you were looking for a blue mushroom, but it went missing several times and so has been replaced by a small loc-n-loc container. The cache is not at the posted coordinates! To find Mario's Blue Toadstool, you will need to solve this puzzle:
Good luck! You can check your answer on Geochecker.com.