Do you have to have a dragon amulet for tattoos on Dragon Fable

if you mean on your dragon, then yes. if you are talking about on your character, i have never heard of it.
you have to have completed the fire orb saga to have any of the tattoos on your dragon, and also you must have visited lady Celestia and done a quest for her to be able to wield the primal elements (which are what the tattoos is)