The Unknown Order

Alright, so I'm worldbuilding for a book idea right now and I need to decide which way I'm going to describe something. 

The evil(ish) magic users in this setting have a certain type of deadly assassin creature that are called Smilers in world. That's important, I'll get to ut later. They can look completely like a human, but once they attack they drop their disguise. They have long manipulatable claws on their hands and slightly off proportions, but their main defining feature is their face. They don't have a mouth, but kinda to compensate they have a very large nose and big eyes, topped by bushy eyebrows and a small forehead.

My main point of contention is deciding what their mouth area looks like. I'd appreciate if you could tell me which option seems scariest/creepiest.

Option One: Nothing, just unblemished skin. I like this one, but feel it might be a bit too bland.

Option Two: A painted smile, kinda like the Joker, but without an actual mouth inside. I don't know what it would exactly look like, but just some sort of tattoo thing that is permanently smiling. I like this one too, and it was my original idea, but I kinda think it might be too goofy for the serious tone of the world.

Option Three: A sort of shriveled up mouthlike line, kinda Deadpool (not the current one, the old one) esque, with stitching appearing to seal it shut. Not so sure about this one, it kinda feels like it would attract attention away from the upper part of the face, which is kinda the opposite of what I want to do, but I think it's probably the creepiest.

So your input would be much appreciated, this is bugging my mind and I'd really like some extra opinions.