Mr.

Come on guys, whatever is inside this box can't be bad at all. It definitely wasn't hidden, rather created by magic of friendship. If you look closely: it's almost like a fruit of the tree of harmony, a final, magical artefact created by friendship. Since the beginning of season 2 i paid much attention to all pieces of plot connected with Discord. All we know is that he was Equestria's oryginal ruler, defeated by Luna and Celestia, later reformed by Fluttershy. I don't know why but since the very beginning I can't negate one of my theories: what if Celestia wanted to reform Discord since the very beginning and make him Equestria's ruler again? I suspect, that whatever is inside this box is mentioned for him. But what can it be? Again: i suspect it's a kind of magical artefact, probably mentioned to change his nature. If Twilight turned into an alicorn, wouldn't it be possible for Discord to turn into Acord, a spirit of harmony (or something like that) thanks to power of friendship itroduced to him by ponies?