During its early years, The Walking Dead only used its comic book source material as a guideline, adapting key moments and the general structure but diverging widely when it came to characters, conflicts, and most importantly, deaths.
Since showrunner Scott Gimple took the reigns in season 4 however, the show has adapted comic book material at an increasing rate with each new season.
Season 7 especially was almost beat for beat the same as its comic counterpart, with Negan's scenes in particular essentially being cut directly from the pages of the book and pasted straight onto the screen.
Resulting in some of the show's most memorable moments, The Walking Dead is at its best when it's adapting material straight from the source, and fortunately there's still plenty of iconic comic book moments that could make their way to the small screen.
With that said though, the show still likes to make major changes here and there, and not every fan-favourite moment is guaranteed to be adapted. With All Out War about to kick off though, there are some major moments that absolutely need to be given the live-action treatment when the show returns later in October.