The Jailer didn't create Frostmourne

Na, Ner’zhul was just an old orc who made a bad deal and ended up paying for it. The Jailer - aka Zovaal - is an Eternal One who predates that orc and just about everything and everyone we know.

I think that he either ruled a domain which we haven’t seen yet, or acted as the Arbiter. The blasted pedestal in Oribos was probably where he stood and where he was taken down, as it were. Why? Well, I think he rebelled. In the Collectors Edition Art book it says:

“…and so it was decreed that he would be condemned to the Maw where he would forever be its Jailer…”

So he didn’t start there, he was sent there for committing something that the powers of the Shadowlands (or somewhere else??) considered to be so heinous that an apt punishment was to spend an eternity in the Maw.

We literally see the Runecarver create them in a cutscene.

Could be this is what they mean by the Light made a deal with the enemy of all.

The Light forsakes it’s Lightforged and Champions to death as part of some ‘deal’?

Hes not though just watch the cutscene… hes not holding the actual items but the Etheral version… meaning it isnt physically real… he just took the schematics.

[Jailer Obtains Frostmourne Cutscene - Vessels of Domination [World of Warcraft: Shadowlands Lore] - YouTube](https://www.youtube.com/watch?v=oZge6jUGtAg)

Different hands. He’s not the dang Primus

I think the power of the Helm came from the crystal inside, and the crystal that the Jailer pulls from the portal and is hammered into Shalamourne probably does the same thing.