The next episode should be roughly issue #83, I thought at the beginning of the season and still think the finale will be issue #100.  I wouldn't mind original material, the only thing I will say is when the show tried to branch off on their own it's been noticeably worse (essentially everything they did with the guvnuh storyline...that whole god awful Beth storyline).  The only difference would probably be Terminal but that was essentially 2 episodes before it just became the Hunters storyline.  

 

If you like the show, you'd probably love the comics...you'd probably like the comics even if you hate the show, the telltale games also have a pretty good original story. 

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