Frozen chests in Dark Forest

[chriscw97]

So one day i was chillaxing in Dark Forest and as usual i went for the treasure chests to see if i could get some more gold but it wasn't what i expected to look like:
http://img443.imageshack.us/img443/4833/img0354j.png

This is not a major bug but i just thought it was funny to see frozen boxes in Dark Forest:)

[Omglolwtfbbq]

I have seen those in ao2 or ao3, I don't remember..
too bad they don't drop special loot or something :D