Originally Posted by
IgnisVenom
So, we know that Vol'jin is missing in action, and maybe he's even dead, and, there have been a few theories, and, I decided to, well, expand them. Keep in mind, this will be quite a long text, I believe, but I'll split this into three parts and put a tl;dr in all of them.
I- The Zandalari
The Zandalari tribe isn't in a very good position. As we learned from Cho, Rastakhan didn't want to listen to Zul, which ended up with the capital of the Zandalari being flooded. Rastakhan couldn't keep the Zandalari safe, so they turned to Zul, who later lead the Zandalari in Pandaria, which didn't end up too well. Now, I believe that Rastakhan was dethroned, and the new king of Trolls is Zul. Now, if that's the case, then we can be sure that the people of the Zandalari have no problem with dethroning someone who isn't doing their job well. If that's the case, then Zul will surely do everything in his power to ensure the safety of his people. Meanwhile, it's very likely that Rastakhan still has followers, and I doubt he is very happy since he was dethroned.
tl;dr: Rastakhan is dethroned, Zul becomes the king of the Trolls and does everything he can to keep his title.
II- Vol'jin
So, the Legion is coming, and, obviously, they are the biggest threat yet. Realizing that we will need help to face Legion, or any other bigger threat, he tells Sylvanas that he will fake his death and that she will have to take over as the Warchief. It made sense for someone more experienced in leading an army to lead the Horde in it's darkest hour. After faking his death, he heads off to find Zul, and offers him and the Zandalari to join the Horde. Zul doesn't have any other choice, so the Zandalari join the Horde.
tl;dr: Vol'jin fakes his death, finds Zul and convinces him to join the Horde.
III- The Aftermath
The number of the Trolls in the Horde drastically increases, and we finally get a few well established Trolls. Rastakhan wants revenge, and that opens up a new potential Troll raid. Blizzard said they would like to do subraces, and this way we could get to play Forest Trolls.
tl;dr: We get well known Troll characters other than Vol'jin, a new storyline with Rastakhan, a possible new subrace.