The other three items are further chapters of Telltale’s series: The Walking Dead: A New Frontier, The Walking Dead: The Final Season, and The Walking Dead: Michonne.
The second is The Walking Dead: The Telltale Definitive Series.
Skybound Games, the series’ new owner, has gathered the whole series and more in a new The Walking Dead Humble Bundle on PC.
The Walking Dead: A New Frontier is the third season of the series, with a new focal character, Javier Garcia.