There is only one enemy I consistently run away from in the Final Fantasy series. I'll bet most of you can guess which recurring enemy it is in two guesses. Here's a picture:
He may be so damn cute but depending on the game, a stab by its knife will deal 90% damage, 9999 damage, or automatically kill you. It also has some pretty decent HP and defense in most FF games, meaning it's difficult to kill.
Terrifying looking? Not in the least. But I do run almost every time rather than fight so that does say something about the fear this thing puts into me.
And I am not alone here. Here's a picture from DeviantArt that about sums it up: