Coffin Mimic Ideas

One idea that I think would be fun if I ever run Curse of Strahd again would be for Strahd to have somehow acquired a mimic that looks like a coffin. He has placed it in an "obvious" location in Castle Ravenloft so that any people who enter his castle seeking to catch him in his slumber might be attacked by it before they can find his real resting place

Obviously, a normal mimic stat block would work just fine in this scenario, but I am looking for ideas on how to spice it up a little bit more. Make it more horrific and Ravenloft-ian, so to speak 

Make it a Vampire Mimic.