The Walking Dead showrunner Scott Gimple confirmed on The Talking Dead the show left hints as to who Negan might’ve killed in the season 6 finale. The obvious would be Glenn as seeing a sick Maggie destroyed him, and the decision would honor the comic book fans. However, it seems like the show might give Glenn’s Lucille death to another character.
[Warning: The Walking Dead comic and TV spoilers ahead]
Signs point to Eugene being on the other end of Lucille. The big clue might be in the what Eugene did before taking the RV to act as a decoy to help the group get Maggie to Hilltop. Eugene gave Rick his recipe on how to make bullets. This makes us nervous.
In the comic books, Eugene takes the initiative to create a bullet factory, which comes in had during the all out war between The Saviors, Hilltop, Alexandria, and The Kingdom. The bullets tilt the odds in Rick’s favor and evens out the playing field. Of course, bullets aren’t enought to take down Negan, but they’ll help.
Eugene giving Rick the recipe must be for a reason. The recipe is Chekhov's gun and it will go off eventually. It would be pointless for Eugene to give Rick the recipe if he believed he was going to stick around. Eugene is also the brains of Alexandria, and they need him to plan their next move. Losing Eugene would hurt the group, even if it’s not in the way we think.
It’s not the first time we’ve seen character deaths from the comics be swapped with another character. For example, it was actually Tyrese who was beheaded by the Governor at the prison in the comic books rather than Herschel in the show. Herschel’s death was better fit for the show, so Eugene getting Glenn’s death might make sense in the context of the scene.
Still, it’s anyone’s game at this point. Even if it’s not Eugene, we know we’ll be devastated once The Walking Dead Season 7 shows us who Negan murdered.