Really?Varians the obvious first choice, also Jaina. Infact more so Jaina, she uses her magic to dispose of Varian and lock him in an arcane prison, and assume the throne, while anduin is absent.
This causes a rift in the alliance between those wanting to destory the horde outright, and those standing against it, causing rifts in the faction.
It will of course end with Jaina either being killed or imprisoned herself like she did Varian, but its Anduin who leads the charge against her alongside Baine, against the Jaina loyalists.
The fallout with cause dalaran to shift back to a neutral state, with one of the remaining council members leading it.
To be frank, Jainas the best the alliance has going for it for some inner faction conflict, because no other leader is really all that, maybe except Genn, but I'd see him siding with Jaina.
It never ceases to amaze me how people get so into their hate for a character for acting naturally, that they either forget or fail to realise that that character no longer acts on those impulses anymore.
As in the case of Jaina she was effectively neutered by Kalec threatening to dump her if she didn't stop hating on the Horde. So unless something happens to said blue dragon Jaina ain't doing anything.
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Been done before, always by people that insist that "Varian must die".How about something like this...
Anduin's ship goes missing after leaving Exodar to return home. Varian Wrynn, out of his mind with worry, orders the Alliance to scour Azeroth to find him. His wrecked ship is located with evidence of Night Elf involvement. King Wrynn, questions Tyrande about it and discovers that Malfurian has sensed something stirring in the Emerald Nightmare and is unavailable. She denies involvement in Anduin's disappearance and is offended that Wrynn would even suspect the Night Elves of involvement. This leads to some tension between the Night Elf leadership and the rest of the Alliance.
Valen arrives in Stormwind and tells Varian that he can feel where Anduin is located, but something is preventing him from going there and Anduin is in great peril. He tells him he can feel him in the mountains of Western Tristfall. He gives the king a crystal that will lead him to his son. Varian assembles some of his greatest heroes (feeling sending a military unit will provoke the Forsaken, choses to send a small unit of trusted and powerful heroes) and heads off to find Anduin. The crystal leads them to the Whispering Forest and they discover a group of Night Elves attempting to sacrifice Anduin. The Night Elves are under the influence of the Emerald Nightmare and while rescuing Anduin, Varian catches a fleeting glimpse of Malfurion steping into a portal to the Emerald Dream. Anduin is rescued and while recovering tells his father and Valen that Malfurion has been corrupted by the Emerald Nightmare and was behind his abduction. Valen senses that something is not quite right with Anduin but Varian ignores him.
Varian demands Malfuion and Tyrande come to Stormwind to explain. When they arrive, they are upset at being summoned but deny any involvement in Anduin's disappearance and the attempted sacrifice. Malfurion says the Emerald Nightmare is stirring and he needs to return to find out what is behind its awakening and to try to keep it contained. He and Tyrande leave and that night, Varian Wyrnn is attacked and slain by Malfurion. Anduin becomes king and demands that the Night Elves turn over Malfurion for trial or there will be war between the Night Elves and the rest of the Alliance. The Council of the Three Hammers, Gelbin Mekkatorque, and Genn Greymane all support Anduin's claim, but Valen councils that something is not right and will not participate in any attack on the Night Elves. Aysa Cloudsinger and the Tushi Pandaren also express their concerns and will not condone any action as well. Valen leaves vowing to find out what has really happened.
Skipping ahead to the resolution, Anduin has been corrupted by N'Zoth and is really his agent to foster chaos in order to attempt to break free of his prision. Malfuion is innocent and did not kill Varian Wyrnn. Once the old god is dealt with, and Anduin's corruption is purged, he is still King of the humans, but won't be the leader of the Alliance. Instead, a council is formed to lead the Alliance consisting of all the leaders of the Alliance and the Dwarves, Gnomes, Worgen, and Draenei take the forefront of the Alliance.