Rotate the right face of the lid 90 degrees to the right, line it up with the rightmost outline of the chest, and then pixel the inside of the lid.
If you want to animate it, use a similar process, but add an aditional frame between these two with a 45 degree rotation of the lid.
From this perspective you can't easily show that the chest is empty, but if you were to add some cobwebs to the hinges of the opened lid, it would help to give the idea that the chest hasn't seen much use.