Self moving entities libgdx

Hi everybody,
I’m new in this forum and i’d like first to tank you for this great community.
Actually i’m working on a game for android platforms, i’m experienced with the android sdk but i have never worked with libgdx before, so i’d like to ask you a question about self moving characters.
In my game i have the main character which can be moved to left and right, and it moves on top by itself, don’t care too much about it, the main issue is:
How can i create self moving enemies? the will not do nothing special, just walk from the leff to the right of the screen and vice versa.
Do i have to use Scene2D?