CONJUNCTURE: The following theory is highly speculative, and is solely based on what we know as of 17:10 May 4th, 2015. (EST)
Theory #4: Hey, VoodooVince....
So I promised theories, and here they are. First off on the list is Slester. First, some backstory: "Slester" was originally a fan-made name for what we now call "God". From what we know of Slester's appearance, it is a small (as in, smaller than the Face) voodoo doll that has been pinned open. Here are my thoughts: Slester is going to be a hallucination/spirit that will cause the cameras (or possibly the whole screen) to behave similarly to how it appears when the "ENDGAME" option is selected; i.e., exhibiting large amounts of glitches and static. It may only appear in Pirate Caverns, and it may be what's in the ( Suit)case. But that's just speculation. A GAME SPECULATION! Thanks for reading!