Do we know what he did to get locked in the Maw?
I’ve been questing through Maldraxxus and the Primus says that zovaal committed some kind of “treachery” and was imprisoned in the Maw for it. However the Primus said he suspects he didn’t act alone
So what did he do? And who was helping him with this mysterious “treachery”?
I’m so curious 
Well…it all started a very long time ago when the Jailer was just a wee lad & he knew he wasn’t supposed to get into that jar of cookies!! We all of course know how all that turned out…
You know how you keep mysteriously losing a sock? That’s him.
MBA in Jail sciences.
A mystery to be unraveled later, if at all. My personal guess: The Jailer isn’t the Final Boss, something else is in the Maw, something that made him what he is
he did not do anything to deserve his fate those other tool bags decided he wasn’t one of the cool kids. and and exile him to a realm of death full of psychopaths
Could be he accepted a truth all others deny…
Sure don’t!
I think he stole all the chocolate from the Caretakers and they got mad, went on strike, and then the other Fancy Pants Ones got mad about the strike and said “GIVE THEM THEIR M&Ms!” And he said, “WHAT WILL YOU DO, THROW ME IN THE MAW?!” And then they did!
he looked at the Arbiter funny.
Your theory is very possible with the corruption schemaw of Blizzard!
Sylvanas is controlling him, making him think he’s been controlling her this whole time.
We don’t know yet, and we may never know.
The best we can guess at is that some how he went against what their creator’s wanted.
The info we have about the First Ones suggests that they showed up in the Shadowlands and organized it. Creating the covenant leaders and the Arbiter, giving each of them a specific role to play. Then they buggered off somewhere else.
Then for some reason the Jailer rebeled against their purpose and the others felt they needed to lock him away to protect that purpose.
My personal suspicion is that the Jailer wanted to conquer the other realms where the other leaders were happy just doing their jobs organising the dead and running the realm of death. The fact that Denathrius has always been with the Jailer in secret and in 9.1 (spoiler) it gets confirmed that Denathrius is the creator of the Dread Lords it makes sense.
You have Denathrius using the Dread Lords to infiltrate, sabotage and pit the other realms against one another for thousands upon thousands of years to soften them up for when the Jailer finally breaks free to take over all of existence.
He majored in Criminology, obtaining his degree after five years at Harvard.
Sailor Sam found the Band on the Run
what if he used to fight death and eventually became depressed and sough to end all life as a way to stop things from dying?
Why though? Why would a being of Death be depressed by things dying? That would be like a Void Lord being depressed by driving things mad, or a Wild God being depressed things being born.
It’s more likely that he saw the other realms gaining power in reality and desired some of that power for himself.
Kill everything so that Death would be the dominant power, not kill everything to stop things from dying.
Is that why revendreth is falling apart, or do the big dudes harvest walls for sinstones? Because they seriously need to stop and get to work fixing all those holes.
i was paraphrasing Sargeras’ story in shadowlands context.
I’m probably wrong but I dont think the ancient evil is the jailer. I think there’s someone else pulling the strings.
The jailer was the example they made to keep everyone in line (stealing his key and relegating him to the maw)
And the arbiter was either killed by the jailer and they tried to resurrect her with his key or she was created to replace him and gradually lost all power (being she was created by them without them truly understanding what they were doing)
However it’s also possible it’s all on its face. the jailer stole the arbiters key, they locked him away, and he wants revenge