The breaking of the machine of death is what allowed the Jailer to set in motion his plans by siphoning all dead souls to the Maw. The machine broke around the start of Legion. It's possible that Sargeras/Kil'jaeden had formed an alliance with the Jailer, maybe keeping Sylvanas obscure to this (since she was their enemy).
I really don't think the machine of death breaking around the time of Legion was a coincidence. Maybe the Felstorm ripped open above the Tomb by Gul'dan somehow pierced the veil and hurt the machine. The sky was basically broken, akin to what Sylvanas did in Icecrown.
The Void. A force of infinite hunger. Its whispers have broken the will of dragons... and lured even the titans' own children into madness. Sages and scholars fear the Void. But we understand a truth they do not. That the Void is a power to be harnessed... to be bent by a will strong enough to command it. The Void has shaped us... changed us. But you will become its master. Wield the shadows as a weapon to save our world... and defend the Alliance!
Well the Legion do recuit and demonize (demonification?) mortal races. This means that they no longer enter the Shadowlands depriving the maw of souls?
Not a great reason i admit.
Also if the jailer needs Azeroths world souls rhen that also a reason to oppose the Legion.
Well... our friend Sylvie has been remarkably uninterested about Azeroth's world soul, so far. But I guess it can be retconned as well
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I wish I could be naive enough to think that Blizzard stories might make sense in 2020
Hey im just trying to think of reasons.
Also the world souls only started bleeding after the Legion at which point she started gathering up blood. If she reckoned timescale wise she could launch the jailer plan before Azeroth died then it makes sense not to prioritise healing it.
If that is the case, which remains to be seen. Right now I think it best to assume that what we know of the Nathrezim remains true - they are natural demons, born in the Nether, and immortal unless killed in the manner prescribed for demons (e.g. death in the Nether or via a few known alternatives). If they were originally natives of the Shadowlands then the axiom still stands true - Shadowlands beings aren't mortal either, they're spirit beings. So even if the Nathrezim originally rose from the Shadowlands they'd be something other than mortal, and then they became demons who are otherwise immortal.
"We're more of the love, blood, and rhetoric school. Well, we can do you blood and love without the rhetoric, and we can do you blood and rhetoric without the love, and we can do you all three concurrent or consecutive. But we can't give you love and rhetoric without the blood. Blood is compulsory. They're all blood, you see." ― Tom Stoppard, Rosencrantz and Guildenstern are Dead
She had Varimithras at her side for many years. IMO she and Varimithras were both on the same page - serving death. Sargeras probably found out Vari was being duplicitous which is why he was being punished in Antorus, and during the Battle of UC he took the fall and Sylvanas could just scapegoat him.
he cant simply sent a group of demonic "adventures" like we did countless time?
The Void. A force of infinite hunger. Its whispers have broken the will of dragons... and lured even the titans' own children into madness. Sages and scholars fear the Void. But we understand a truth they do not. That the Void is a power to be harnessed... to be bent by a will strong enough to command it. The Void has shaped us... changed us. But you will become its master. Wield the shadows as a weapon to save our world... and defend the Alliance!
The Void. A force of infinite hunger. Its whispers have broken the will of dragons... and lured even the titans' own children into madness. Sages and scholars fear the Void. But we understand a truth they do not. That the Void is a power to be harnessed... to be bent by a will strong enough to command it. The Void has shaped us... changed us. But you will become its master. Wield the shadows as a weapon to save our world... and defend the Alliance!