Ed gets separated from Al alongside Envy & Lin inside of Gluttony’s belly. Essentially the thing inside his belly is an artificial portal of truth created by their father. Essentially what feels like game over for the 3 of them is not a surprise that Ed gets into a fight with Envy. Though you can’t blame them because the homunculi are literally the reason the war with the Ishmal happened. As it was their trigger, and for that reason, all the Ishbalans died as sacrifice for the philosopher’s stone. Kind of showing they only view humans as a resource.
Ed’s idea is if they go through the real portal, they can get back to the surface. Though of course everything has a cost, which is where the term equivalent exchange comes into play. As the philosopher’s stone that is bound to Envy is from the Ishblan people, they can be a source for the 3 of them to get back home. Of course it hurts Ed to sacrifice the souls, but it is a fucked situation where he has no choice. Plus Envy’s point that the souls can never come back to their bodies.
Before they return, we see that there are two portals of truth. It makes sense that Ed and Al are connected through their souls because Ed was able to retrieve Al’s soul. At the very least, Ed is connected to Al’s soul. Meaning it is more than possible for Al to get back to his original body. The problem is the cost for Al to get it and how to open the portal of truth. Though as soon as Ed gets back, we see that both Gluttony and Al are with Father. Who looks very much like Hohenheim. Which is bizarre, granted Hohenheim himself is quite strange in and of himself.
Sadly for Roy, the corruption in the military is more deep-rooted than he realized. More people at the top know that Bradley is a homunculus and that the Ed Brothers are indeed sacrifices. Roy took a gamble, and now his team is disbanded, so I’m curious what he can even do now.
What is most interesting is that Bradley wasn’t always a homunculus, which is probably where he differs from the others. They conducted experiments on who could conquer the Philosopher’s Stone. It makes sense why Bradley can age and he has human qualities to him. Curious if that affects him going forward.