In the "Epilogue" scene that comes before the credits, we see the Big Boss enter a room, pick up a piece of paper, scratch something out on it with a marker and then crumple it up in anger.
I realize that with the poor lighting, the smaller resolution and the compression it was hard to make out what exactly was on that paper. Some people also told me during previews that they had no idea what it was...so here it is in its rawest form! It's just a paper full of Batman villains, some of which we may even see in future episodes!
The point of the image and the epilogue was to show that this Big Boss had plans for Batman, and that he was using an arsenal of villains to "cripple" him. He scratches out The Riddler, indicating that he's been defeated and is now useless to him. Hope that clears up any confusion with the epilogue scene!
-Phil