Okay, so a lot of theories are being spat around about who got Lucille'd at the end of the Walking Dead Season 6 Finale. Although a lot of them are well founded...a lot of them are also missing very vital things that happened in the end scene of the show.
So, let's finally put everything that could possibly be put into our 'cauldron of theory' and see what comes out. What I mainly aim to do is provide the reader with enough information to make their own decision and not claim to fully solve the mystery.
Although, I will be voicing my opinions with reasons throughout.
Was it Rick, Carl, Sasha, Glenn, Maggie, Abraham, Eugene, Rosita, Daryl or Aaron?
Let's begin by ruling out who we can. Firstly, Negan made a statement about "ripping the boys other eye out and feeding it to his father" which surely rules Rick or Carl out of biting the dust for one big reason. If Negan was just going to kill either Rick or Carl anyway then his statement wouldn't have any strength as the leverage he was trying to use to keep people quiet and so there would be no point in saying it. As Rosita and Maggie made up the "and you are" bit of Negan's rhyme to decide who would have the honour of meeting the lovely Lucille, I doubt he'd go right back to them. That doesn't rule them out but coupled with the fact Maggie is with child and that Rosita hasn't been developed enough yet for her death to give enough fear to Negan, I'm going to scratch them off this list. For similar reasons, I think it would be silly to have the death be Aaron as well since, surely, the writers would want Negan's big entrance to be one that shocks viewers so that they stay afraid of him. The only thing that would make Sasha a contender, in terms of siginificance, is her length of time in the show and newfound relationship with Abraham that could leave our favourite redhead heartbroken and hungry for revenge.
That leaves us with Glenn, Daryl, Micchone, Abraham, Sasha and Eugene.
When Negan approaches the person getting their head bashed in, he appears to come toward them from their right (implying it couldn't be the very end person on Rick's right which is Glenn) and we also see Negan's shadow go across Rick's face as he approaches his victim, and this shadow moves to Rick's left (implying the victim is on Rick's left). Now, the only people on Rick's left (in order) are Sasha, Aaron, Carl and Eugene.
Now, this is where things get both extremely interesting and very confusing.
Right before Negan destroys our beloved victim, he appears to glance to his right and left at people when he is speaking. However, the glance to the right is much more prominent. This adds to theory that Negan has chosen someone who isn't on the right of Rick and that it must be someone on the left. If the glance to the left was at a member of the group then it rules out it being the very end person (Eugene) and leaves only Sasha. If it, however, turns out that Negan's slight glance to his left was at his men, then it's highly probable that it's Eugene biting the dust and his recent character development (as well as him handing over the plan to make bullets to Rick) would give him the significant impact required to be such a big blow to the franchise and leave a hole in our hearts. Unless it is just Aaron but surely the Walking Dead wouldn't do something that lazy? I love Aaron and everything but he just isn't a big enough character yet and hasn't been there long enough for his death to make Negan menacing enough.
What if the Walking Dead writers ignored all the camera angles and shadows and line ups and just chose who they wanted anyway?
Well, good question my guys, gals, cats, dogs and aliens from outer-space. The writers could very well do this and just pick someone they would think is a big enough character. If that were the case and we had to evaluate the people on Rick's right too I would probably say it wasn't Micchone. I thought it could be for a while but I have faith in the Walking Dead to not be lazy and kill off another Rick Grimes love interest so soon after the last one. Especially after people being annoyed at there being a cliff-hanger, I believe the writers will be extra careful when stitching together episode one of season seven. That leaves Daryl, Glenn and Abraham on Rick's right. Let's get the obvious one out of the way. It was Glenn who fulfilled the role of meeting the worse end of Lucille in the comic books so it would be ridiculous to rule him out. He is such a huge character with such emotional significance that his death would leave a massive void in the hearts of everyone on and off the show.
I don't think it would be Daryl purely because I feel like he has a lot to his story left. He has unfinished business with Dwight and there's always something with him and Carol. Also, since he is injured because Dwight shot him, that would lead me to believe that Negan would conclude that killing someone who is injured wouldn't make him look scary enough and he'd want to go for someone who appears stronger.
Thus, Abraham. Abraham has been built up in the series recently and has emotional substance with Sasha and is a very strong character that would be able to "take it like a champ" and already showed himself to be strong in front of Negan when he raised up to him. I think this would make Abraham a good choice for Negan if he wanted to take out "the big guy" in order to inflict fear into the group. Abraham also died the way that nurse Denise died in the show but in the comics instead. The Walking Dead like to switch around deaths so they may have been saving Abraham for something bigger impact. Then again, he may want someone that strong to work for him and supposedly leaked audio from the finale that is slowed down appears to show Abraham shouting "Nooooooo.
Essentially, it boils down to Glenn, Eugene and Abraham being the prime choices if the writers ignore how the finale was cut together. If they do, however, take notice of that then Sasha and Eugene appear to be the only two logical options.
Personally, I think Eugene's character would carry more of a punch than Sasha's right now (even with her stuff with Abraham) so I would say it was him but we don't know what the Walking Dead writers might be thinking. In theory, for the biggest impact they would go with someone from the Atlanta group that has a big stake in the show like Glenn or Daryl.
Overall, I'd say the way the show was cut together that it would have to be Eugene or Sasha and if Negan was talking to the group on his left then that leaves Sasha. Eugene is my bet if we're taking all the camera angles and shadows as fact. It's hard but I'm locking that in. Ahhh.
Unless, again, it's Aaron but surely not!? Aaron was one of the stronger looking ones when Negan was choosing but surely he has a lot more development required yet. Maybe even taking care of Maggie if Glenn bites the dust?