This crate is available for 1000 MC from August 11-25, 2011. From September 22-November 3, 2011 you could have received one Serpent Hedge Mystery Crate by purchasing 26000 MCs from the offers page. The description reads "Contains a complete Naga, Dragon, or Hydra hedge. Which one? You'll have to open it to find out...".
What's inside[]
One of the following sets:
Dragon[]
Which includes:
Naga[]
Which includes:
Hydra[]
Which includes: