I've never seen him/it
Nunca lo he visto actuar de esta manera.
I've never seen him act this way.
— El hombre de la Tierra (2007)
Yo también salgo por la noche y nunca lo he visto.
I also go out at night and I've never seen him.
— Las noches de Cabiria (1957)
I've never seen him around here.
I've never seen it.
En realidad, nunca lo he visto.
Actually, I’ve never seen it.
I've never seen him in my life.