If I was able to piece together all those damn kanji components correctly, then I think this is the phrase:
垂量調整用食べられません。ご開封後、捨てて下さい。
I can't read most of it, but from what I can gather from autotranslation, it's either a choking hazard warning or a warning that you shouldn't eat some part of the packaging. LOL I think the second sentence says "After opening, please throw (it) away." If I had to hazard a guess as to what this thing is for, it's to sit your figurines on if you want some additional height -- somewhere in the translation is mentioned "vertical adjustment". Someone with real competency in Japanese will need to comment further.

I enjoy trying, though.
Unfortunately, I'm 99% confident that it's not some epic quote or phrase about the game or anything!
