n'conspik
A person who’s so stealthy, they can sneak up on you and then whisper 'you’re dead' in your ear while you’re still trying to breathe.
He snuck up on me in the hallway and said 'you’re dead' so quietly I almost believed it.
She was behind me the whole time and I didn’t even notice until she said 'you’re dead'.
He walked into the room like he was invisible and then said 'you’re dead' and I got scared.