For "The Walking Dead," the Negan war gaveth, and the Negan war tooketh away. But in the final analysis, the two full seasons that the AMC series devoted to its prosecution became a drawn-out slog, one which finally came to an emotional, somewhat predictable, literally merciful end with Sunday's eighth-season finale.On the plus side, Jeffrey Dean Morgan's portrayal of Negan brought a major infusion of energy and genuine menace to the show — a welcome jolt for any series this late in its run. But waging the war — with all the tactical machinations of what was billed as "All Out War," strewn across the 16 episodes of Season 8 — at times felt as if the plot was ambling along like a zombie, or more accurately, running in place.This season was punctuated by some key deaths and arresting moments. Unexpectedly, there were no major casualties in the finale, which pivoted in somewhat telegraphed fashion on the unlikely character of Eugene (Josh McDermitt), whose bullet-making efforts turned out to be a clever double-cross, leaving Negan's forces decimated.Answering the pleas of his late son, Rick (Andrew Lincoln) spared Negan's life, saying — in words teased earlier in the season — that "My mercy prevails over my wrath."Earlier in the season, the show included a gauzy flash-forward sequence that depicted a bearded Rick and pointed toward a more harmonious future — one in which Negan, jarringly, still had a place. After all that transpired, and Negan's defiant words in the penultimate episode, it was hard to envision how that could be anything but fantasy.Related: 'Fear the Walking Dead' gets major makeover with Morgan's arrivalViewers now know that scenario is a possibility, although the finale shrewdly planted the seeds for future discord (this is a drama, after all), emanating from those who had been Rick's closing allies. Letting Negan live caused Maggie (Lauren Cohan) to break down — craving vengeance for her husband — and her decision to plot against Rick was joined by, among others, Daryl (Norman Reedus), potentially placing the show's most significant players in conflict.Whether that prospect is enough to jump-start interest in the series remains to be seen. Viewing of "The Walking Dead" has already fallen off pretty dramatically, a byproduct of age, the overall gravity of a saturated TV marketplace and yes, missteps that the program has made along the way."We are worse than we were," Morgan (Lennie James) told Rick near the finale's outset, a reference to their lost humanity, but also a fair description of where the show stands — commercially as well as creatively — compared to its dizzying apex.Despite the departure of Morgan to join "Fear the Walking Dead," the show must do relatively little reloading, a challenge it has regularly faced (and one of the things that has kept the narrative fresh), sometimes with uneven results.Obviously, "The Walking Dead" is too much of a cash cow for AMC to part with the show blithely, but at this point, it wouldn't be crazy to start contemplating an end game, one that would allow viewers to follow Rick's story, at least, toward some sort of natural conclusion.In his dying appeal to his dad, Carl asked Rick to do some soul-searching, and find his way back to a more hopeful place. Rick took the advice to heart, in a finale that exhibited flashes of the show's underlying strengths. But nothing on TV lives forever, and for the character, as well as the series, that plea might have come a bit too late.