"I am still here" was in every single game since FNaF3.



FNaF3 - First teaser



FNaF4 - Ending



FNaFSL - Said by Ennard in the Private Room



FNaFWorld - Intro



You can go check if you want, it's not a FNaF3/FNaF6 exclusive thing. Scott just loves that sentence I guess.