Luke's Reapperance
So you have probably heard a million ways on how Luke will be coming back. Well, I have my own theory.
First of all, Luke can't take on Carver's whole group. But we know he wouldn't just take off and run.
What if, Luke came back with a group that way he could take on Carver's group?
Remember this guy? It's Roman from 400 days. Why was he dead in the beginning? It seems his group got into a gun fight (or something like that) with another group. There are two possibilities of how this went down.
Either Carver's group came and shot them down, or it could of been a different group,one that's had a past experience with Roman.
Well, lets say this group was the 400 days characters. There heading up to Wellington too right? That means that they are going the same direction as Clem and the Cabin group. What if hypothetically, they were around the area that everyone is in? That means Christa could of ran into them. What if the gun shot that fired in the beginning when Christa was out looking for wood, was the 400 days group attacking the bandits? It was a off-screen supposed death, so we don't know fully what happened. And if you don't think Christa would of survived, look at Kenny.
We know that Bonnie is for whatever reason with Carver and not the 400 Days characters. This I'm not entirely sure about. But we can acknowledge the fact the Bonnie has always been sort of a weak character. I think for whatever the reason she went with Carver she was in a sense manipulated. Manipulated to think that the Cabin group is bad. (It would explain why she is surprised when they handed her a lot of food.) And manipulated to think that Carver is good.
So in the end how does this all puzzle together? Well, I believe Luke is going to somehow run into the 400 days characters. I feel like they both will have the same motive. (either destroying Carver, or getting Bonnie back.) And that will be Luke's group when he tries to rescue the group. I feel like it won't be until later on in Episode 4 when there will be a lot of bloodshed. Think about the cover picture of Episode 4.There will be Carver's group,400 Days, The Cabin Group, Zombies, and what's left of the Season 1 characters.
EDIT: To add to this, I think Eddie (The guy from 400 days Wyatt's friend) will be at Carver's camp.