Open the box

ENGLISH Game for Trijam#288 with the theme “Break a box and see what happens”. (I'll warn you right away, it took me way tooooooo long to make this game, so I'm absolutely ineligible. I'm submitting it anyway, though, because it ties in with the theme, and hey, the game's done now). What's that strange box? Should I open it? And how? (Turn on the sound, it's essential to the gameplay. The Engl…